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1.
Curr Biol ; 34(10): R498-R501, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38772337

ABSTRACT

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.


Subject(s)
Beekeeping , Stress, Physiological , Bees/physiology , Animals , Beekeeping/methods , Systems Theory
2.
Elife ; 122024 Mar 13.
Article in English | MEDLINE | ID: mdl-38477669

ABSTRACT

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.


Subject(s)
Basal Ganglia , Knowledge , Neural Networks, Computer , Neurons , Systems Theory
4.
PLoS Comput Biol ; 20(2): e1011867, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38422161

ABSTRACT

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.


Subject(s)
Family , Systems Theory , Humans , Phylogeny , Gene Regulatory Networks/genetics , Morphogenesis/genetics , Biological Evolution
5.
Biosystems ; 236: 105123, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38244715

ABSTRACT

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.


Subject(s)
Ecosystem , Systems Theory , Thermodynamics , Entropy , Biological Evolution , Ecology
6.
J Eval Clin Pract ; 30(2): 330-336, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37723831

ABSTRACT

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.


Subject(s)
COVID-19 , Emergency Medicine , Humans , COVID-19/epidemiology , Systems Theory , Delivery of Health Care , Systems Analysis
7.
J Theor Biol ; 576: 111655, 2024 01 07.
Article in English | MEDLINE | ID: mdl-37944592

ABSTRACT

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.


Subject(s)
Systems Biology , Systems Theory , Systems Analysis
8.
Article in English | MEDLINE | ID: mdl-37569057

ABSTRACT

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.


Subject(s)
Telerehabilitation , Humans , Outpatients , Finland , Systems Theory , Occupational Therapists
9.
Curr HIV/AIDS Rep ; 20(4): 206-217, 2023 08.
Article in English | MEDLINE | ID: mdl-37486568

ABSTRACT

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.


Subject(s)
HIV Infections , Sexual and Gender Minorities , Male , Humans , Homosexuality, Male , HIV Infections/epidemiology , HIV Infections/prevention & control , Systems Theory , Sexual Behavior
10.
Biosystems ; 229: 104925, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37182834

ABSTRACT

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.


Subject(s)
Cognition , Consciousness , Causality , Systems Theory , Personal Autonomy
11.
Int J Inj Contr Saf Promot ; 30(2): 153-154, 2023 06.
Article in English | MEDLINE | ID: mdl-37230121

Subject(s)
Safety , Systems Theory , Humans
12.
J Prim Care Community Health ; 14: 21501319231163123, 2023.
Article in English | MEDLINE | ID: mdl-37078521

ABSTRACT

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.


Subject(s)
COVID-19 , Pandemics , Pregnancy , Female , Humans , United States , Systems Theory , Delivery of Health Care , Communication
13.
J Hist Behav Sci ; 59(4): 417-432, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37119535

ABSTRACT

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.


Subject(s)
Psychoanalysis , Humans , Psychoanalysis/history , Freudian Theory/history , Personality , Personality Disorders , Systems Theory
14.
PLoS One ; 18(3): e0282482, 2023.
Article in English | MEDLINE | ID: mdl-36862686

ABSTRACT

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.


Subject(s)
Interpersonal Relations , Self Concept , Female , Humans , Male , Cross-Sectional Studies , Spain , Systems Theory , United States
15.
BMC Emerg Med ; 23(1): 22, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36855096

ABSTRACT

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.


Subject(s)
Neoplasms , Systems Theory , Humans , Emergency Service, Hospital , Nurse's Role , Triage , Neoplasms/therapy
16.
Nurs Sci Q ; 36(2): 152-157, 2023 04.
Article in English | MEDLINE | ID: mdl-36994958

ABSTRACT

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.


Subject(s)
Enterocolitis, Necrotizing , Infant, Newborn, Diseases , Infant , Infant, Newborn , Humans , Infant, Premature , Systems Theory
17.
Biosystems ; 226: 104872, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36921792

ABSTRACT

Formalization of autopoiesis is an ongoing effort among theoretical biologists. In this field, Letelier and co-authors proposed that Robert Rosen's (M,R)-systems theory be used as a formalism for autopoiesis. In (M,R)-systems theory, Rosen proposes that one solve a set of functional closure equations (FCEs) which account for all of the components of the system as coming from within the system itself. A key part of the functional closure equations is the repair of the metabolism component of the system. Rosen's theory gives the organizational closure of the components as well as their products, as found in autopoiesis. However, according to Razeto-Barry (M,R)-systems leaves out some of the messiness and approximation that we find in autopoiesis as he reformulates it. A related problem is that though FCEs have a long history, they are difficult in practice to solve due to their mathematical formulation. In this paper we give a novel exact solution for the FCEs for continuous real vector-valued functions which is nevertheless difficult to compute. In addition we propose an extended form of FCEs which both captures more of the messiness of autopoiesis and also helps to make the FCEs more solvable. Finally, we use our solution for the extended FCEs to give an extended repair function for a metabolism taken from a representative class of biological dynamics for gene expression (the repressilator). More generally we show that one can use our solution for the extended FCEs to get an extended repair function for continuous real vector-valued functions.


Subject(s)
Plant Leaves , Systems Theory , Mathematics
18.
Res Theory Nurs Pract ; 37(1): 84-100, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36792315

ABSTRACT

Objective: Examination of community resilience after Hurricane Harvey and -applicability of Neuman's systems model to the role of public health nurses in applying primary, secondary, and tertiary prevention strategies to communities susceptible to natural disasters. Design: Descriptive, exploratory study. Sample: A convenience sample (N = 1,470). Measurements: Hurricane Harvey Survey. Results: Respondents from seven counties in southeast Texas report previously experiencing a hurricane (80%) with no weather-related flooding (79%), adequate preparation (54%), failure to comprehend the potential severity of Hurricane Harvey (62%), damage to their homes (45%), and a 68% loss of personal belongings. Anxiety, frustration, disbelief, determination, and hopefulness were rated highest after the storm. Residents received updates from family and friends, social media, and online news reports regarding rising water, even though, in many cases, a mandatory evacuation was not officially announced. Only 35% of respondents reported being aware of resources available, possibly due to flooding or inaccessibility of typical resources (e.g., hospitals, shelters). Communicating through social networks (social media, family, and friends) provided avenues for arranging evacuations and assistance. Respondents report giving assistance to others and receiving assistance from family, friends, and their faith community. The majority of respondents reported that the community provided adequate services during the hurricane (59%), and they plan to stay in southeast Texas (70%). Conclusions: Southeast Texas residents demonstrated individual and community resilience which may be further supported with primary, secondary, and tertiary nursing interventions as illustrated by Neuman's systems model. The rise in positive emotional response traits demonstrates positive coping, which is consistent with resilience. Effective and timely communication through social networks provides an additional line of resistance to protect and promote the resilience of the community. The lack of medical resources indicates a break in the normal line of defense and an area for potential improvement with the utilization of mobile medical units to provide healthcare for areas not easily accessible during a disaster. Public health nurses are strategically positioned in the international community to lead prevention and recovery efforts by applying theory-based community interventions.


Subject(s)
Cyclonic Storms , Humans , Public Health Nursing , Systems Theory , Texas , Surveys and Questionnaires
19.
J Osteopath Med ; 123(4): 207-213, 2023 04 01.
Article in English | MEDLINE | ID: mdl-36628949

ABSTRACT

Osteopathic medicine is a holistic, patient-specific approach. Explaining the impact of osteopathic manipulative medicine (OMM) has been problematic because many of its effects are nonlinear. Complex systems theory (CST) is explored as a mechanism of understanding the interplay of the body's anatomy and physiology, an illness process, and the effects of OMM. Tensegrity is discussed as an example of an emergent property of the body's systems that affects not only biomechanics but also pathophysiology. Previous explanations of osteopathic philosophy are reviewed. The Host + Disease=Illness paradigm is a way to think through the impact of host and disease factors on an illness state, and how targeted interventions may affect the illness. The Osteopathic 5 Models are another way to view the body's complexity. The area of greatest restriction (AGR) screen can be understood to direct OMM in a way that respects complexity and enables asymmetric and nonlocal results to realize health potential. The impact of this framework is in coherently explaining the impact of osteopathic philosophy and OMM and exploring new approaches to research.


Subject(s)
Manipulation, Osteopathic , Osteopathic Medicine , Osteopathic Physicians , Humans , Systems Theory
20.
Ergonomics ; 66(3): 377-405, 2023 Mar.
Article in English | MEDLINE | ID: mdl-35723619

ABSTRACT

The capability of current Ergonomics methods to capture dynamism is limited, stifling our understanding of work-as-done, distributed situational awareness and organisational drift. This paper provides a demonstration of concept of DynEAST; an extension of the EAST framework underpinned by principles from Dynamic Network Analysis, to capture elements of dynamism within work systems. The DynEAST concept is applied to a railway maintenance case study. Case study findings demonstrate how DynEAST outputs can be used to advance our understanding of the aforementioned phenomena and better equip practitioners for current and future Ergonomics challenges.Practitioner summary: This paper introduces the DynEAST method. DynEAST enables HF/E practitioners to model and analyse dynamic features of complex work systems. The development of DynEAST is timely due to the concurrent proliferation of increasingly complex sociotechnical systems and stagnation of HF/E methods development; particularly those able to model systemic dynamism. Abbreviations: DynEAST: dynamic event analysis of systemic teamwork; EAST: dynamic event analysis of systemic teamwork; HF/E: human factors and ergonomics; HF: human factors; DNA: dynamic network analysis; HTA: hierarchal task analysis; CWA: cognitive work analysis; CAST: causal analysis based on system theory; STAMP: system theoretic accident model and processes; FRAM: functional resonance analysis method; SNA: social network analysis; DSA: distributed situational awareness; PPO: possession protection officer; PO: protection officer; RTS: railway track signals; LPA: local possession authority; SMEs: subject matter experts.


Subject(s)
Awareness , Systems Theory , Humans , Ergonomics/methods , Systems Analysis
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