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1.
Curr Biol ; 34(10): R498-R501, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38772337

RESUMO

A new study showcases the usefulness of systems theory and network analyses for understanding how dozens of stressors can act concomitantly to affect managed honey bee health. Interestingly, the most influential stressors are not those currently being addressed by beekeepers.


Assuntos
Criação de Abelhas , Estresse Fisiológico , Abelhas/fisiologia , Animais , Criação de Abelhas/métodos , Teoria de Sistemas
2.
JAMA Psychiatry ; 81(6): 618-623, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568615

RESUMO

Importance: Psychiatric disorders may come and go with symptoms changing over a lifetime. This suggests the need for a paradigm shift in diagnosis and treatment. Here we present a fresh look inspired by dynamical systems theory. This theory is used widely to explain tipping points, cycles, and chaos in complex systems ranging from the climate to ecosystems. Observations: In the dynamical systems view, we propose the healthy state has a basin of attraction representing its resilience, while disorders are alternative attractors in which the system can become trapped. Rather than an immutable trait, resilience in this approach is a dynamical property. Recent work has demonstrated the universality of generic dynamical indicators of resilience that are now employed globally to monitor the risks of collapse of complex systems, such as tropical rainforests and tipping elements of the climate system. Other dynamical systems tools are used in ecology and climate science to infer causality from time series. Moreover, experiences in ecological restoration confirm the theoretical prediction that under some conditions, short interventions may invoke long-term success when they flip the system into an alternative basin of attraction. All this implies practical applications for psychiatry, as are discussed in part 2 of this article. Conclusions and Relevance: Work in the field of dynamical systems points to novel ways of inferring causality and quantifying resilience from time series. Those approaches have now been tried and tested in a range of complex systems. The same tools may help monitoring and managing resilience of the healthy state as well as psychiatric disorders.


Assuntos
Transtornos Mentais , Humanos , Transtornos Mentais/psicologia , Resiliência Psicológica , Teoria de Sistemas
3.
JAMA Psychiatry ; 81(6): 624-630, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568618

RESUMO

Importance: Dynamical systems theory is widely used to explain tipping points, cycles, and chaos in complex systems ranging from the climate to ecosystems. It has been suggested that the same theory may be used to explain the nature and dynamics of psychiatric disorders, which may come and go with symptoms changing over a lifetime. Here we review evidence for the practical applicability of this theory and its quantitative tools in psychiatry. Observations: Emerging results suggest that time series of mood and behavior may be used to monitor the resilience of patients using the same generic dynamical indicators that are now employed globally to monitor the risks of collapse of complex systems, such as tropical rainforest and tipping elements of the climate system. Other dynamical systems tools used in ecology and climate science open ways to infer personalized webs of causality for patients that may be used to identify targets for intervention. Meanwhile, experiences in ecological restoration help make sense of the occasional long-term success of short interventions. Conclusions and Relevance: Those observations, while promising, evoke follow-up questions on how best to collect dynamic data, infer informative timescales, construct mechanistic models, and measure the effect of interventions on resilience. Done well, monitoring resilience to inform well-timed interventions may be integrated into approaches that give patients an active role in the lifelong challenge of managing their resilience and knowing when to seek professional help.


Assuntos
Transtornos Mentais , Humanos , Transtornos Mentais/psicologia , Transtornos Mentais/terapia , Resiliência Psicológica , Teoria de Sistemas
4.
Elife ; 122024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477669

RESUMO

Oscillations arise in many real-world systems and are associated with both functional and dysfunctional states. Whether a network can oscillate can be estimated if we know the strength of interaction between nodes. But in real-world networks (in particular in biological networks) it is usually not possible to know the exact connection weights. Therefore, it is important to determine the structural properties of a network necessary to generate oscillations. Here, we provide a proof that uses dynamical system theory to prove that an odd number of inhibitory nodes and strong enough connections are necessary to generate oscillations in a single cycle threshold-linear network. We illustrate these analytical results in a biologically plausible network with either firing-rate based or spiking neurons. Our work provides structural properties necessary to generate oscillations in a network. We use this knowledge to reconcile recent experimental findings about oscillations in basal ganglia with classical findings.


Assuntos
Gânglios da Base , Conhecimento , Redes Neurais de Computação , Neurônios , Teoria de Sistemas
6.
PLoS Comput Biol ; 20(2): e1011867, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38422161

RESUMO

Determining the general laws between evolution and development is a fundamental biological challenge. Developmental hourglasses have attracted increased attention as candidates for such laws, but the necessity of their emergence remains elusive. We conducted evolutionary simulations of developmental processes to confirm the emergence of the developmental hourglass and unveiled its establishment. We considered organisms consisting of cells containing identical gene networks that control morphogenesis and evolved them under selection pressure to induce more cell types. By computing the similarity between the spatial patterns of gene expression of two species that evolved from a common ancestor, a developmental hourglass was observed, that is, there was a correlation peak in the intermediate stage of development. The fraction of pleiotropic genes increased, whereas the variance in individuals decreased, consistent with previous experimental reports. Reduction of the unavoidable variance by initial or developmental noise, essential for survival, was achieved up to the hourglass bottleneck stage, followed by diversification in developmental processes, whose timing is controlled by the slow expression dynamics conserved among organisms sharing the hourglass. This study suggests why developmental hourglasses are observed within a certain phylogenetic range of species.


Assuntos
Família , Teoria de Sistemas , Humanos , Filogenia , Redes Reguladoras de Genes/genética , Morfogênese/genética , Evolução Biológica
7.
Biosystems ; 236: 105123, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38244715

RESUMO

In this paper we explore the relevance and integration of system theory and thermodynamics in terms of the Earth system. It is proposed that together, these fields explain the evolution, organization, functionality and directionality of life on Earth. We begin by summarizing historical and current thinking on the definition of life itself. We then investigate the evidence for a single unit of life. Given that any definition of life and its levels of organization are intertwined, we explore how the Earth system is structured and functions from an energetic perspective, by outlining relevant thermodynamic theory relating to molecular, metabolic, cellular, individual, population, species, ecosystem and biome organization. We next investigate the fundamental relationships between systems theory and thermodynamics in terms of the Earth system, examining the key characteristics of self-assembly, self-organization (including autonomy), emergence, non-linearity, feedback and sub-optimality. Finally, we examine the relevance of systems theory and thermodynamics with reference to two specific aspects: the tempo and directionality of evolution and the directional and predictable process of ecological succession. We discuss the importance of the entropic drive in understanding altruism, multicellularity, mutualistic and antagonistic relationships and how maximum entropy production theory may explain patterns thought to evidence the intermediate disturbance hypothesis.


Assuntos
Ecossistema , Teoria de Sistemas , Termodinâmica , Entropia , Evolução Biológica , Ecologia
8.
J Appl Psychol ; 109(6): 871-896, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38270988

RESUMO

Recognizing the challenges that conflict poses, organizational researchers have invested considerable energy toward investigating the processes by which conflict occurs and spreads within a team. However, current theoretical frameworks of conflict contagion posit a static growth trajectory in which members become engaged in conflict and stay in conflict. While this trajectory is certainly possible, the broader conflict literature outside of the organizational sciences has shown evidence for a more varied set of potential trajectories of conflict contagion. To advance theory on team conflict, we integrate conflict research from micro-level (interpersonal) to macro-level (interstate) perspectives into a formal theory of intrateam conflict contagion. Drawing from conflict stage and social contagion theory, we theorize that team members move through three stages of conflict (disengaged, at-risk, engaged) at rates determined by four process mechanisms (faultlines, forgiveness, frustration, integration) such that disengaged individuals become at-risk of engaging in conflict, engage in conflict, then disengage, only to potentially become at risk of reengaging at a later point in time. Using computational modeling, we demonstrate the generative sufficiency of our theory to account for conflict trajectories observed in the broader conflict literature. To facilitate the interpretation of such trajectories, we present a typology of contagion trajectories, discuss the dynamic properties of these trajectories (e.g., stability, bifurcations), and provide implications for future theory building and practice. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Conflito Psicológico , Processos Grupais , Humanos , Teoria de Sistemas , Emprego/psicologia , Adulto
9.
J Eval Clin Pract ; 30(2): 330-336, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37723831

RESUMO

RATIONALE: COVID-19 has fundamentally changed the practice of Emergency Medicine (EM). Care delivery on the front lines has historically depended upon ostensibly reliable input-output models for staffing, supplies, policies, and therapies. Challenged by the complexity of healthcare during the pandemic, the fallibility of these reductionist models was quickly revealed. Providers and systems quickly had to reconceptualize their dependence on the wider, complex system in which healthcare operates and find adaptive solutions to rapid changes. AIMS/METHOD: This papers seeks to review and describe how Systems Thinking and Complexity Theory (ST/CT)-concepts, principles, and tools that can be used to understand and impact our constantly evolving health system-can be applied to better understand and enact change in complex settings such as during COVID-19. Some of these ST/CT are described through the real world example of the Alameda Health System Vaccine Taskforce. RESULTS: ST/CT concepts such as Unintended Consequences, Interrelationships, Emergent Behavior, Feedback Loops, and Path Dependence can help EM providers and planners understand the context in which their system operates. Key principles such as Collaboration, Iterative Learning, and Transformational Leadership can help these actors respond to current and future challenges. The integration of these concepts and principles into the Learning Health System offers a model for tying these key concepts and principles together into an adaptive, cross-sectoral organizational approach. CONCLUSION: By integrating ST/CT into the practice of EM, we can not only improve our ability to care for patients but also our capacity to understand and strengthen our wider systems of care.


Assuntos
COVID-19 , Medicina de Emergência , Humanos , COVID-19/epidemiologia , Teoria de Sistemas , Atenção à Saúde , Análise de Sistemas
10.
J Theor Biol ; 576: 111655, 2024 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-37944592

RESUMO

Michael Savageau's Biochemical Systems Analysis I, II, IIIpapers, published in volumes 25 and 26 of the journal,kickstarted a research programme that originated many of the core concepts and tools of Systems Biology. This article briefly summarizes these papers anddiscusses the most relevant developments in Biochemical Systems Theory since their publication.


Assuntos
Biologia de Sistemas , Teoria de Sistemas , Análise de Sistemas
11.
Annu Rev Public Health ; 45(1): 7-25, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38100647

RESUMO

We present a detailed argument for how to integrate, or bridge, systems science thinking and methods with implementation science. We start by showing how fundamental systems science principles of structure, dynamics, information, and utility are relevant for implementation science. Then we examine the need for implementation science to develop and apply richer theories of complex systems. This can be accomplished by emphasizing a causal mechanisms approach. Identifying causal mechanisms focuses on the "cogs and gears" of public health, clinical, and organizational interventions. A mechanisms approach focuses on how a specific strategy will produce the implementation outcome. We show how connecting systems science to implementation science opens new opportunities for examining and addressing social determinants of health and conducting equitable and ethical implementation research. Finally, we present case studies illustrating successful applications of systems science within implementation science in community health policy, tobacco control, health care access, and breast cancer screening.


Assuntos
Ciência da Implementação , Humanos , Política de Saúde , Análise de Sistemas , Determinantes Sociais da Saúde , Teoria de Sistemas , Acessibilidade aos Serviços de Saúde/organização & administração , Pesquisa sobre Serviços de Saúde/organização & administração , Saúde Pública , Neoplasias da Mama
12.
Artigo em Inglês | MEDLINE | ID: mdl-37569057

RESUMO

BACKGROUND: In the development of effective telerehabilitation (TR) interventions, understanding the various characteristics affecting its practice is essential. Remote connection creates a new technically shaped environment for therapy and, therefore, previous therapy methods do not work the same way as before. OBJECTIVE: The objective of this survey was to describe the practice of TR through the socio-technical theory approach. METHODS: The 629 respondents to the online questionnaire included music therapists, occupational therapists, speech and language therapists, physiotherapists, and neuropsychologists. The materials consisted of five open-ended questions. The analysis combined data-based and theory-based analysis. RESULTS: In the data-based content analysis, we identified three main categories and eight generic categories, whereas in the theory-based, we categorised the main results according to the Fit Between Individuals, Tasks, Technology, and Environment (FITTE) framework dimensions. TR is everyday-life based, it requires shared participation, and the approach has to include coaching and collaboration with the client and their close associates. The everyday-life environment is one of the main dimensions that affect all the other dimensions. CONCLUSIONS: TR can be seen as technology-mediated home-based rehabilitation, as it can integrate rehabilitation into the client's everyday life. In TR, therapy becomes multilateral and it creates a new kind of shared partnership into outpatient therapy.


Assuntos
Telerreabilitação , Humanos , Pacientes Ambulatoriais , Finlândia , Teoria de Sistemas , Terapeutas Ocupacionais
13.
Curr HIV/AIDS Rep ; 20(4): 206-217, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37486568

RESUMO

PURPOSE OF REVIEW: Global disparities in HIV infection, particularly among gay, bisexual, and other men who have sex with men (GBMSM), indicate the importance of exploring the multi-level processes that shape HIV's spread. We used Complex Systems Theory and the PRISMA guidelines to conduct a systematic review of 63 global reviews to understand how HIV is socially patterned among GBMSM. The purpose was to conduct a thematic analysis of the reviews to (1) synthesize the multi-level risk factors of HIV risk, (2) categorize risk across the socioecological model, and (3) develop a conceptual model that visualizes the interrelated factors that shape GBMSMS's HIV "risk." RECENT FINDINGS: We included 49 studies of high and moderate quality studies. Results indicated that GBMSM's HIV risk stems from the individual, interpersonal, and structural levels of the socioecological model. We identified a few themes that shape GBMSM's risk of HIV infection related to biomedical prevention methods; sexual and sex-seeking behaviors; behavioral prevention methods; individual-level characteristics and syndemic infections; lived experiences and interpersonal relationships; country-level income; country-level HIV prevalence; and structural stigma. The multi-level factors, in tandem, serve to perpetuate GBMSM's risk of HIV infection globally. The amalgamation of our thematic analyses from our systematic reviews of reviews suggests that the risk of HIV infection operates in an emergent, dynamic, and complex nature across multiple levels of the socioecological model. Applying complex systems theory indicates how multilevel factors create a dynamic and reinforcing system of HIV risk among GBMSM.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Teoria de Sistemas , Comportamento Sexual
14.
Biosystems ; 229: 104925, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37182834

RESUMO

Is information the other face of causation? This issue cannot be clarified without discussing how these both are related to physical laws, logic, computation, networks, bio-signaling, and the mind-body problem. The relation between information and causation is also intrinsically linked to many other concepts in complex systems theory such as emergence, self-organization, synergy, criticality, and hierarchy, which in turn involve various notions such as observer-dependence, dimensionality reduction, and especially downward causation. A canonical example proposed for downward causation is the collective behavior of the whole system at a macroscale that may affect the behavior of each its member at a microscale. In neuroscience, downward causation is suggested as a strong candidate to account for mental causation (free will). However, this would be possible only on the condition that information might have causal power. After introducing the Causal Equivalence Principle expanding the relativity principle for coarse-grained and fine-grained linear causal chains, and a set-theoretical definition of multiscale nested hierarchy composed of modular ⊂-chains, it is shown that downward causation can be spurious. It emerges only in the eyes of an observer, though, due to information that could not be obtained by "looking" exclusively at the behavior of a system at a microscale. On the other hand, since biological systems are hierarchically organized, this information gain is indicative of how information can be a function of scale in these systems and a prerequisite for scale-dependent emergence of cognition and consciousness in neural networks.


Assuntos
Cognição , Estado de Consciência , Causalidade , Teoria de Sistemas , Autonomia Pessoal
15.
Int J Inj Contr Saf Promot ; 30(2): 153-154, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37230121
16.
J Hist Behav Sci ; 59(4): 417-432, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37119535

RESUMO

This article examines Talcott Parsons's efforts at building the theory of personality system as a special case of his general theory of action and places those efforts in historical context. I demonstrate how, during the middle decades of the twentieth century, Parsons employed elements of classic Freudian thought to advance a new appreciation of the personality system and its relations to other action systems. I begin with an overview of the reception of psychoanalysis at the Boston Psychoanalytic Society and Institute, the Massachusetts General Hospital, and the Harvard Department of Social Relations, showing how Parsons's thinking on the personality system cannot be understood apart from his association with these three institutions. I then turn to how Parsons endeavored to integrate his particular brand of sociology with his own interpretation of Freud's writings to explain how the personality system functions and develops. I conclude by showing that while Parsons's involvements with psychoanalysis became more intermittent after the mid-1950s, to the end of his life he remained steadfast in his enthusiasm for Freud's theory of personality. In short, Parsons always believed that for sociological theory to progress, it needed to engage with psychoanalysis.


Assuntos
Psicanálise , Humanos , Psicanálise/história , Teoria Freudiana/história , Personalidade , Transtornos da Personalidade , Teoria de Sistemas
17.
J Prim Care Community Health ; 14: 21501319231163123, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37078521

RESUMO

Perinatal communication is one factor driving racial disparities in maternal and infant morbidity. The murder of George Floyd in May 2020, in addition to the disproportionate impacts of the Covid-19 pandemic on communities of color, was a catalyst for American society to address racial injustices with a renewed sense of urgency. Drawing upon sociotechnical systems (STS) theory, this rapid review describes changes in the literature regarding the organizational, social, technical, and external subsystems that affect communication between perinatal providers and their Black patients. The goal of this work is to support health system optimization of health communication initiatives and, as a result, improve patient experience and parent and child outcomes. As part of a multi-year project designed to improve health communications about safe fish consumption during pregnancy, and in response to racial disparities among our health system's patient population related to receipt of nutrition messages during prenatal visits, we conducted a rapid review of literature on Black parents' experience of all communication while receiving perinatal care. A search of PubMed identified relevant articles published in English since 2000. Articles were screened to include articles that focused on Black people receiving perinatal care. Article content was then coded using deductive content analysis guided by STS theory to inform healthcare system improvement efforts. Differences in the prevalence of codes pre- and post-2020 are compared using chi-square statistics. The search in PubMed yielded 2419 articles. After screening, 172 articles were included in the rapid review. There was an increased recognition of communication as a key component of quality perinatal care after 2020 (P = .012) and of the limitations of standardized technical communication (P = .002) after 2020. Emerging literature suggests improving perinatal health communication and relationships with Black parents would address disparities in perinatal patient and baby outcomes. Healthcare systems must address the racial disparities in maternal and child outcomes. Since 2020, public attention and published research on this issue has increased. Understanding perinatal communication using STS theory aligns subsystems in service of racial justice.


Assuntos
COVID-19 , Pandemias , Gravidez , Feminino , Humanos , Estados Unidos , Teoria de Sistemas , Atenção à Saúde , Comunicação
18.
PLoS One ; 18(3): e0282482, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36862686

RESUMO

OBJECTIVES: In the current study, we examined the relationship between differentiation of self (DoS) and key relationship functioning variables among couples. This is the first study to test such relationships using a cross-cultural longitudinal approach (i.e., samples from Spain and the U.S.) while controlling for stressful life events-a key theoretical construct in Bowen Family Systems Theory. METHODS: A sample of 958 individuals (n = 137 couples from Spain, and n = 342 couples from U.S.) was used in cross sectional and longitudinal models to analyze the effects of a shared reality construct of DoS on anxious attachment, avoidant attachment, relationship stability, and relationship quality while considering gender and culture. RESULTS: Our cross-sectional results indicated that men and women from both cultures experienced an increase in DoS over time. DoS predicted increased relationship quality and stability and decreased anxious and avoidant attachment in U.S. participants. Longitudinally, DoS predicted increased relationship quality and decreased anxious attachment for Spanish women and men, while it predicted greater relationship quality and stability and decreased anxious and avoidant attachment of U.S. couples. Implications of these mixed findings are discussed. CONCLUSIONS: Higher levels of DoS are linked with a better couple relationship across time, despite varying levels of stressful life events. Although some cultural differences regarding the links between relationship stability and avoidant attachment exist, this positive link between differentiation and the couple relationship is mostly consistent across the U.S. and Spain. The implications and relevance for integration into research and practice are discussed.


Assuntos
Relações Interpessoais , Autoimagem , Feminino , Humanos , Masculino , Estudos Transversais , Espanha , Teoria de Sistemas , Estados Unidos
19.
Nurs Sci Q ; 36(2): 152-157, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36994958

RESUMO

Preterm infants have increased morbidity and mortality due to immature physiology and neonatal complications. Necrotizing enterocolitis (NEC) is a devastating gastrointestinal complication that affects morbidity and mortality in preterm infants. The authors present an adaptation of Neuman's systems model called the NEC systems model to explore intrinsic and extrinsic factors leading to NEC in preterm infants. The literature was searched for theoretical models to guide exploration of neonatal disease influenced by the environment. Neuman's Systems Model provides a holistic approach to care of the system, offering a foundation to develop frameworks to examine preterm infants in their environment with associated stressors.


Assuntos
Enterocolite Necrosante , Doenças do Recém-Nascido , Lactente , Recém-Nascido , Humanos , Recém-Nascido Prematuro , Teoria de Sistemas
20.
BMC Emerg Med ; 23(1): 22, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36855096

RESUMO

OBJECTIVES: This study was conducted in 2022 at King Hussein Cancer Center (KHCC) to analyze the queuing theory approach at the Emergency Department (ED) to estimate patients' wait times and predict the accuracy of the queuing theory approach. METHODS: According to the statistics, the peak months were July and August, with peak hours from 10 a.m. until 6 p.m. The study sample was a week in July 2022, during the peak days and hours. This study measured patients' wait times at these three stations: the health informatics desk, triage room, and emergency bed area. RESULTS: The average number of patients in line at the health informatics desk was not more than 3, and the waiting time was between 1 and 4 min. Since patients were receiving the service immediately in the triage room, there was no waiting time or line because the nurse's role ended after taking the vital signs and rating the patient's disease acuity. Using equations of queuing theory and other relativistic equations in the emergency bed area gave different results. The queuing theory approach showed that the average residence time in the system was between 4 and 10 min. CONCLUSIONS: Conversely, relativistic equations (ratios of served patients and departed patients and other related variables) demonstrated that the average residence time was between 21 and 36 min.


Assuntos
Neoplasias , Teoria de Sistemas , Humanos , Serviço Hospitalar de Emergência , Papel do Profissional de Enfermagem , Triagem , Neoplasias/terapia
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