Complex Hierarchy Research Articles

Rethinking the life of court dwarfs in early modern Florence: the case of Pietro Barbino at the Medici court☆

AbstractCourt dwarfs were a feature of aristocratic entourages across Europe from the Medieval period until the eighteenth century and their presence is recorded in both contemporary artworks and written sources. Traditionally, it has been assumed that these courtly attendants functioned solely as jester‐buffoons who were exploited and humiliated by their patrons, but is this assumption accurate? By recovering the forgotten histories of this significant group of court staff, new perspectives emerge on the lives of court dwarfs and the various roles they undertook, beyond their conventional role as jesters. This article examines the case of Pietro Barbino, a dwarf attendant at the Medici court in sixteenth‐century Florence, who was the subject of a portrait by the court sculptor Valerio Cioli. Information from archival sources about Barbino's life, both inside and outside the court, corresponds with Giorgio Vasari's description of him as ‘a gifted dwarf, well‐lettered, a very gentle spirit and a favourite of our Duke’ (Lives of the Artists, 1568). Barbino's story suggests that, at least in some instances, dwarf attendants were involved with more erudite aspects of courtly entertainment and were able to achieve a measure of personal autonomy within the complex hierarchy of the court system.

Sex Differences in Hierarchical and Modular Organization of Functional Brain Networks: Insights from Hierarchical Entropy and Modularity Analysis.

Existing studies have demonstrated significant sex differences in the neural mechanisms of daily life and neuropsychiatric disorders. The hierarchical organization of the functional brain network is a critical feature for assessing these neural mechanisms. But the sex differences in hierarchical organization have not been fully investigated. Here, we explore whether the hierarchical structure of the brain network differs between females and males using resting-state fMRI data. We measure the hierarchical entropy and the maximum modularity of each individual, and identify a significant negative correlation between the complexity of hierarchy and modularity in brain networks. At the mean level, females show higher modularity, whereas males exhibit a more complex hierarchy. At the consensus level, we use a co-classification matrix to perform a detailed investigation of the differences in the hierarchical organization between sexes and observe that the female group and the male group exhibit different interaction patterns of brain regions in the dorsal attention network (DAN) and visual network (VIN). Our findings suggest that the brains of females and males employ different network topologies to carry out brain functions. In addition, the negative correlation between hierarchy and modularity implies a need to balance the complexity in the hierarchical organization of the brain network, which sheds light on future studies of brain functions.

Changing the conversation: impact of guidelines designed to optimize interprofessional facilitation of simulation-based team training

BackgroundInterprofessional simulation-based team training (ISBTT) is commonly used to optimize interprofessional teamwork in healthcare. The literature documents the benefits of ISBTT, yet effective interprofessional collaboration continues to be challenged by complex hierarchies and power dynamics. Explicitly addressing these issues during ISBTT may help participants acquire skills to navigate such challenges, but guidelines on how to do this are limited.MethodsWe applied an educational design research approach to develop and pilot structured facilitator guidelines that explicitly address power and hierarchy with interprofessional teams. We conducted this work in a previously established ISBTT program at our institution, between September 2020 and December 2021. We first reviewed the literature to identify relevant educational theories and developed design principles. We subsequently designed, revised, and tested guidelines. We used qualitative thematic and content analysis of facilitator interviews and video-recording of IBSTT sessions to evaluate the effects of the guidelines on the pre- and debriefs.ResultsQualitative content analysis showed that structured guidelines shifted debriefing participation and content. Debriefings changed from physician-led discussions with a strong focus on medical content to conversations with more equal participation by nurses and physicians and more emphasis on teamwork and communication. The thematic analysis further showed how the conversation during debriefing changed and how interprofessional learning improved after the implementation of the guidelines. While power and hierarchy were more frequently discussed, for many facilitators these topics remained challenging to address.ConclusionWe successfully created and implemented guidelines for ISBTT facilitators to explicitly address hierarchy and power. Future work will explore how this approach to ISBTT impacts interprofessional collaboration in clinical practice.

EnhancerNet: a predictive model of cell identity dynamics through enhancer selection.

Understanding how cell identity is encoded by the genome and acquired during differentiation is a central challenge in cell biology. I have developed a theoretical framework called EnhancerNet, which models the regulation of cell identity through the lens of transcription factor-enhancer interactions. I demonstrate that autoregulation in these interactions imposes a constraint on the model, resulting in simplified dynamics that can be parameterized from observed cell identities. Despite its simplicity, EnhancerNet recapitulates a broad range of experimental observations on cell identity dynamics, including enhancer selection, cell fate induction, hierarchical differentiation through multipotent progenitor states and direct reprogramming by transcription factor overexpression. The model makes specific quantitative predictions, reproducing known reprogramming recipes and the complex haematopoietic differentiation hierarchy without fitting unobserved parameters. EnhancerNet provides insights into how new cell types could evolve and highlights the functional importance of distal regulatory elements with dynamic chromatin in multicellular evolution.

Multiplexed spatial mapping of chromatin features, transcriptome, and proteins in tissues.

The phenotypic and functional states of a cell are modulated by a complex interactive molecular hierarchy of multiple omics layers, involving the genome, epigenome, transcriptome, proteome, and metabolome. Spatial omics approaches have enabled the capture of information from different molecular layers directly in the tissue context. However, current technologies are limited to map one to two modalities at the same time, providing an incomplete representation of cellular identity. Such data is inadequate to fully understand complex biological systems and their underlying regulatory mechanisms. Here we present spatial-Mux-seq, a multi-modal spatial technology that allows simultaneous profiling of five different modalities, including genome-wide profiles of two histone modifications and open chromatin, whole transcriptome, and a panel of proteins at tissue scale and cellular level in a spatially resolved manner. We applied this technology to generate multi-modal tissue maps in mouse embryos and mouse brains, which discriminated more cell types and states than unimodal data. We investigated the spatiotemporal relationship between histone modifications, chromatin accessibility, gene and protein expression in neuron differentiation revealing the relationship between tissue organization, function, and gene regulatory networks. We were able to identify a radial glia spatial niche and revealed spatially changing gradient of epigenetic signals in this region. Moreover, we revealed previously unappreciated involvement of repressive histone marks in the mouse hippocampus. Collectively, the spatial multi-omics approach heralds a new era for characterizing tissue and cellular heterogeneity that single modality studies alone could not reveal.

Twisting vortex lines regularize Navier-Stokes turbulence.

Fluid flows are intrinsically characterized via the topology and dynamics of underlying vortex lines. Turbulence in common fluids like water and air, mathematically described by the incompressible Navier-Stokes equations (INSE), engenders spontaneous self-stretching and twisting of vortex lines, generating a complex hierarchy of structures. While the INSE are routinely used to describe turbulence, their regularity remains unproven; the implicit assumption being that the self-stretching is ultimately regularized by viscosity, preventing any singularities. Here, we uncover an inviscid regularizing mechanism stemming from self-stretching itself, by analyzing the flow topology as perceived by an observer aligned with the vorticity vector undergoing amplification. While, initially, vorticity amplification occurs via increasing twisting of vortex lines, a regularizing anti-twist spontaneously emerges to prevent unbounded growth. By isolating a vortex, we additionally demonstrate the genericity of this self-regularizing anti-twist. Our work, directly linking dynamics of vortices to turbulence statistics, reveals how the Navier-Stokes dynamics avoids the development of singularities even without the aid of viscosity.

Deep learning reveals a damage signalling hierarchy that coordinates different cell behaviours driving wound re-epithelialisation.

One of the key tissue movements driving closure of a wound is re-epithelialisation. Earlier wound healing studies describe the dynamic cell behaviours that contribute to wound re-epithelialisation, including cell division, cell shape changes and cell migration, as well as the signals that might regulate these cell behaviours. Here, we have used a series of deep learning tools to quantify the contributions of each of these cell behaviours from movies of repairing wounds in the Drosophila pupal wing epithelium. We test how each is altered after knockdown of the conserved wound repair signals Ca2+ and JNK, as well as after ablation of macrophages that supply growth factor signals believed to orchestrate aspects of the repair process. Our genetic perturbation experiments provide quantifiable insights regarding how these wound signals impact cell behaviours. We find that Ca2+ signalling is a master regulator required for all contributing cell behaviours; JNK signalling primarily drives cell shape changes and divisions, whereas signals from macrophages largely regulate cell migration and proliferation. Our studies show deep learning to be a valuable tool for unravelling complex signalling hierarchies underlying tissue repair.

Decoding dynamic visual scenes across the brain hierarchy.

Understanding the computational mechanisms that underlie the encoding and decoding of environmental stimuli is a crucial investigation in neuroscience. Central to this pursuit is the exploration of how the brain represents visual information across its hierarchical architecture. A prominent challenge resides in discerning the neural underpinnings of the processing of dynamic natural visual scenes. Although considerable research efforts have been made to characterize individual components of the visual pathway, a systematic understanding of the distinctive neural coding associated with visual stimuli, as they traverse this hierarchical landscape, remains elusive. In this study, we leverage the comprehensive Allen Visual Coding-Neuropixels dataset and utilize the capabilities of deep learning neural network models to study neural coding in response to dynamic natural visual scenes across an expansive array of brain regions. Our study reveals that our decoding model adeptly deciphers visual scenes from neural spiking patterns exhibited within each distinct brain area. A compelling observation arises from the comparative analysis of decoding performances, which manifests as a notable encoding proficiency within the visual cortex and subcortical nuclei, in contrast to a relatively reduced encoding activity within hippocampal neurons. Strikingly, our results unveil a robust correlation between our decoding metrics and well-established anatomical and functional hierarchy indexes. These findings corroborate existing knowledge in visual coding related to artificial visual stimuli and illuminate the functional role of these deeper brain regions using dynamic stimuli. Consequently, our results suggest a novel perspective on the utility of decoding neural network models as a metric for quantifying the encoding quality of dynamic natural visual scenes represented by neural responses, thereby advancing our comprehension of visual coding within the complex hierarchy of the brain.

Photoacoustic imaging for three-dimensional bioprinted constructs

Bioimaging is used to inspect the successful growth and functional differentiation of cells in printed biomaterials, which are ultimately finalized into functional artificial tissues capable of replacing native tissues. While optical bioimaging techniques are commonly utilized, the current trend in three-dimensional (3D) bioprinting towards replicating complex 3D microarchitectures poses a challenge for conventional optical imaging techniques in providing clear cross-sectional images due to the opaque nature of tissue. Consequently, these limitations necessitate lengthy and destructive preparation processes, which are associated with sacrificing cell viability and damaging the bioprinted material. Photoacoustic imaging (PAI) is a versatile imaging technique that extends the advantages of the optical bioimaging technique to undiscovered depths enabled by its acoustic hybridity, making itself a promising tool for non-destructive imaging of 3D bioprinted constructs. In this review, we introduce the flexible spectral contrasts provided by PAI, which are potentially applicable to 3D-bioprinted constructs, and summarize bioprinting studies that functionally implement PAI for in vitro and in vivo assessments. Finally, we provide an outlook on practical considerations for the more complete integration of these two fields, anticipating more fruitful discoveries as bioprinting advances towards more complex hierarchies.

Theoretical and Experimental Approaches to Study of Biological Objects by Mathematical Methods Using the Example of Hormone Production in the Thyroid Gland

The study of any biological object is a complex process that involves a number of successive stages, one of which tools can be a specially created expert system. It is advisable to present the conclusion about the studied biological object in clear forms of expression – quantitative or binary, which are the results of the practical application of the principles of absorption by some researched factors of others, a compromise between them or the prevailing alternative of the studied properties. The involvement of mathematical technologies in the identification and explanation of the regularities of the activity of biological objects requires the display of the results of their research using a mathematical language. This makes it possible to establish regularities in the course of biological processes and predict their consequences. Since any living system is formed from a large number of elements, the organism has a complex hierarchy of structural and functional levels of organization. A mandatory prerequisite for the activity of a biological system is a variety of states, each of them being characterized by its own characteristics – markers of change, which, according to the degree of completeness of the one state transformation into another, should be divided into markers of primary changes, markers of prevailing majority changes, and markers of final changes. Comprehensive application of the Semi-quantitative analysis of electronograms according to Ryabukha O. (2000) and her method for determining the profiles of hormonopoietic cells’ special capacities (2003) when studying the cytophysiology of the thyroid gland in normal and pathological conditions, it is possible to determine the specific link of the follicular cell’s specialized activity, in which there was a violation of hormonopoiesis, and to assess its intensity. The developed Conceptual apparatus of functional connections between organelles of hormone-producing cells when studying them by the Method of correlation analysis by creating intra- and intersystem correlation portraits reflects the features of mutual influences and interdependencies, which deepens the understanding of the intimate mechanisms of hormonopoiesis.

Tailored Hollow Mesoporous Carbon Nanospheres from Soft Emulsions Enhance Kinetics in Sodium Batteries.

Mesoporous materials endowed with a hollow structure offer ample opportunities due to their integrated functionalities; however, current approaches mainly rely on the recruitment of solid rigid templates, and feasible strategies with better simplicity and tunability remain infertile. Here, we report a novel emulsion-driven coassembly method for constructing a highly tailored hollow architecture in mesoporous carbon, which can be completely processed on oil-water liquid interfaces instead of a solid rigid template. Such a facile and flexible methodology relies on the subtle employment of a 1,3,5-trimethylbenzene (TMB) additive, which acts as both an emulsion template and a swelling agent, leading to a compatible integration of oil droplets and composite micelles. The solution-based assembly process also shows high controllability, endowing the hollow carbon mesostructure with a uniform morphology of hundreds of nanometers and tunable cavities from 0 to 130 nm in diameter and porosities (mesopore sizes 2.5-7.7 nm; surface area 179-355 m2 g-1). Because of the unique features in permeability, diffusion, and surface access, the hollow mesoporous carbon nanospheres exhibit excellent high rate and cycling performances for sodium-ion storage. Our study reveals a cooperative assembly on the liquid interface, which could provide an alternative toolbox for constructing delicate mesostructures and complex hierarchies toward advanced technologies.

Flow-through moisture meter for measuring grain moisture as part of an automated grain moisture control system

The methods of increasing the accuracy and efficiency of the production process, as well as ensuring high quality of final products in the grain processing industry, are investigated. It is shown that to solve the problem of insufficient quality control of grain materials, an automated system for monitoring the properties and characteristics of bulk granular materials is necessary. The features of the construction of automatic and automated systems for monitoring the properties and characteristics of bulk granular materials are considered. Measurement methods and control devices of the main technological parameters used in the management of grain processing facilities are briefly described. It is proposed to include a flow moisture meter in the automated grain moisture control system. The physical properties of grain and grain materials, measurement conditions and instrumentation for grain moisture control are analyzed. The use of devices based on the dielkometric method in the subsystem of an automated process control system is discussed. The application of intelligent sensors of a measuring system with a complex multilevel hierarchy is described. The structure of the interconnection of measuring devices for intellectual support of humidification processes and quality control of the studied materials is given. A functional diagram and metrological characteristics of a prototype grain moisture monitoring device, a flow moisture meter, are presented. The metrological characteristics of this device meet the requirements of the grain processing industry and allow it to be used as part of a humidity control system

Tangled Banks, Braided Rivers and Complex Hierarchies: Beyond Microevolution and Macroevolution.

Ever since the Modern Synthesis, a debate about the relationship between microevolution and macroevolution has persisted - specifically, whether they are equivalent, distinct, or explain one another. How one answers this has become shorthand for a much broader set of theoretical debates in evolutionary biology. Here, we examine microevolution and macroevolution in the context of the vast proliferation of data, knowledge, and theory since the advent of the Modern Synthesis. We suggest that traditional views on microevolution and macroevolution are too binary and reductive. For example, patterns and processes are not confined to micro- and macro- domains; they are interconnected at various temporal and spatial scales and across hierarchical entities. Further, biological entities have variably fuzzy boundaries, and evolutionary processes that influence macroevolution occur at micro- and macro- levels. In addition, these conceptual advances in phylodynamics have yet to be fully integrated with contemporary macroevolutionary approaches. Finally, holding microevolution and macroevolution as distinct domains thwarts synthesis and collaboration on important research questions. We propose that the focal entities and processes considered by evolutionary studies be contextualized within the newfound complexity of the multidimensional, multi-modal, multi-level phylogenetic system.

A detailed 3D stoichiometric map of spinels and oxides in structurally critical passivation layers on Inconel 718 superalloy after heating up to 650 °C

This research presents a detailed structure and time evolution for forming the passivation layer during oxidation of Selective Laser Melted (SLM-IN718) and commercially cast (Comm-IN718) Inconel 718 at 650 °C. It reveals that this layer has a complex 3D structure, with a top layer of Fe-Ni Chromite spinels (NiFexCr(2−x)O4) and a sublayer of Cr2O3. Raman maps and statistical analysis estimate x in NiFexCr(2−x)O4 for different heating times. The heating process initially forms iron-rich NiFexCr(2−x)O4 with x≈2, decreasing to ≈1 after 72 h of heating for both Comm- and SLM-IN718. Interestingly, a slightly different result was observed for the heat-treated SLM sample (HTSLM-IN718), where x increased again to 1.2 and 1.4 after 72 h. Secondary Ion Mass Spectrometry (SIMS) results reveal the depth hierarchy of the passivation layer profile, with the chromite layer covering a thicker Cr2O3 layer forming above the niobium-rich intermetallic layer above the alloy. Passivation layers are critical to the endurance of superalloys during extreme thermal cycling conditions. Therefore, by precisely determining the complex stoichiometry and hierarchy of the layer, this study can guide the development of durable superalloys with improved resistance to extreme thermal cycling conditions.

Using multi‐scale spatial models of dendritic ecosystems to infer abundance of a stream salmonid

Abstract Understanding patterns of species abundance is essential for planning landscape‐level conservation. The complex hierarchies of dendritic ecosystems result in different levels of heterogeneity at distinct geographic scales. Species responses to dynamic environmental drivers may also vary spatially depending on their interactions with landscape features. Monitoring abundance by explicitly quantifying their spatial and temporal variation is important for strategic management. We analysed brook trout (Salvelinus fontinalis) count data collected from 173 sites in western North Carolina between 1989 and 2015. We developed a Bayesian hierarchical model that used single‐ and multi‐pass electro‐fishing data and characterized their respective capture probabilities. We quantified spatial variation using a multi‐scale process model representative of the nested stream habitats, and we investigated differences in population temporal trends and responses to seasonal weather patterns by space and life stage. Trout abundance was lower on the Atlantic slope of the Eastern Continental Divide than in the interior, on average, and the Atlantic slope juveniles were more adversely affected by high winter flows. However, Atlantic slope populations of both lifestages demonstrated positive temporal trends, whereas Interior juveniles demonstrated a negative trend. We found higher spatial variation than temporal variation in abundance when conditioned on the covariates, where the primary source of spatial heterogeneity was revealed at the segment level, compared to watershed or network levels. Our multi‐scale spatial model outperformed simpler models in abundance estimation and out‐of‐sample prediction. The inferred per‐pass capture probabilities indicated that single‐pass surveys were as efficient as multi‐pass surveys. Synthesis and applications. Our study suggested conservation priority should involve multiple criteria, including present‐day abundance, temporal trend and sensitivity to environmental drivers. Based on the inferred scale‐specific variations in trout abundance, we recommend that future surveys strategically combine single‐pass surveys with multi‐pass surveys to optimize abundance estimation. Our approach is widely applicable to other species and ecosystems occupying dendritic habitats.

Biomechanical functions analysis of the Mallard webbed foot: A study of macroscopic and microscopic material assembly and tendon morphology

The mallard webbed foot represents an exemplary model of biomechanical efficiency in avian locomotion. This study delves into the intricate material assembly and tendon morphology of the mallard webbed foot, employing both macroscopic and microscopic analyses. Through histological slices and scanning electron microscopy (SEM), we scrutinized the coupling assembly of rigid and flexible materials such as skin, tendon, and bone, while elucidating the biomechanical functions of tendons across various segments of the tarsometatarsophalangeal joint (TMTPJ). The histological examination unveiled a complex structural hierarchy extending from the external integument to the skeletal framework. Notably, the bone architecture, characterized by compact bone and honeycombed trabeculae, showcases a harmonious blend of strength and lightweight design. Tendons, traversing the phalangeal periphery, surrounded by elastic fibers, collagen fibers, and fat tissue. Fat chambers beneath the phalanx, filled with adipocytes, provide effective buffering, enabling the phalanx to withstand gravity, provide support, and facilitate locomotion. Furthermore, SEM analysis provided insights into the intricate morphology and arrangement of collagen fiber bundles within tendons. Flexor tendons in proximal and middle TMTPJ segments adopt a wavy-type, facilitating energy storage and release during weight-bearing activities. In contrast, distal TMTPJ flexor tendons assume a linear-type, emphasizing force transmission across phalangeal interfaces. Similarly, extensor tendons demonstrate segment-specific arrangements tailored to their respective biomechanical roles, with wavy-type in proximal and distal segments for energy modulation and linear-type in middle segments for enhanced force transmission and tear resistance. Overall, our findings offer a comprehensive understanding of the mallard webbed foot's biomechanical prowess, underscoring the symbiotic relationship between material composition, tendon morphology, and locomotor functionality. This study not only enriches our knowledge of avian biomechanics but also provides valuable insights for biomimetic design and tissue engineering endeavors.

Phosphorylation Code of Human Nucleophosmin Includes Four Cryptic Sites for Hierarchical Binding of 14-3-3 Proteins

Nucleophosmin (NPM1) is the 46th most abundant human protein with many functions whose dysregulation leads to various cancers. Pentameric NPM1 resides in the nucleolus but can also shuttle to the cytosol. NPM1 is regulated by multisite phosphorylation, yet molecular consequences of site-specific NPM1 phosphorylation remain elusive. Here we identify four 14-3-3 protein binding sites in NPM1 concealed within its oligomerization and α-helical C-terminal domains that are found phosphorylated in vivo. By combining mutagenesis, in-cell phosphorylation and PermaPhos technology for site-directed incorporation of a non-hydrolyzable phosphoserine mimic, we show how phosphorylation promotes NPM1 monomerization and partial unfolding, to recruit 14-3-3 dimers with low-micromolar affinity. Using fluorescence anisotropy we quantified pairwise interactions of all seven human 14-3-3 isoforms with four recombinant NPM1 phosphopeptides and assessed their druggability by fusicoccin. This revealed a complex hierarchy of 14-3-3 affinities toward the primary (S48, S293) and secondary (S106, S260) sites, differentially modulated by the small molecule. As three of these 14-3-3 binding phosphosites in NPM1 reside within signal sequences, this work suggests a mechanism of NPM1 regulation by which NPM1 phosphorylation can promote 14-3-3 binding to affect NPM1 shuttling between cell compartments. It also provides further evidence that phosphorylation-induced structural rearrangements of globular proteins serve to expose otherwise cryptic 14-3-3-binding sites that are important for cellular function.

The Dynamics of Power in Dramatic Discourse: A Stylistic Analysis of the Arabic Drama Bab Al-Hara

This study explores the linguistic indexes of power dynamics through the lens of linguistic politeness and impoliteness in Arab media discourse. This objective was achieved through examining Abu Shawkat's utterances systematically utilizing well-established politeness theories, impoliteness paradigms, plus cooperation principles. The examination delves into Abu Shawkat’s patriarchal authority and its impact on their discursiveness from the viewpoint of complex societal interplays involving power relations, social distance assessments and imposition. Characters skillfully employ varied strategies of both politeness and impoliteness techniques alongside slight offensiveness methods for effectively navigating these subtly shifting landscapes to ultimately achieve various social objectives. The study emphasizes the need for comprehending politeness theories when navigating complex dramatic dialogues. Face-threatening acts and politeness strategies determine the relative power dynamics in the conversation between dramatic characters. In addition to that, this analysis shows how impoliteness can create complex authority hierarchies whilst simultaneously claiming autonomy within a narrative structure. This study in conclusion amplifies our understanding of the linguistic interplay weaved within dramatic discourse, primarily if it is tied deeply with Arab cultural nuances.

Understanding prison living: Mitigating the problem of ‘incompatible’ incarcerated people through the perspectives of correctional officers

AbstractPrisoner incompatibility is a challenge for correctional officers (COs), as incompatible people in prison are more likely to engage in negative interactions, participate in altercations, cause harm to each other and create tension on a unit. Through in‐depth semi‐structured interviews with 28 COs employed in Atlantic Canada, we explore how incompatibility among incarcerated people shapes how incarcerated people are managed and perceived by COs. Engaging the prison design literature, we further examine the kinds of spatial designs and protocols that contribute to, or mitigate, incompatibility. We find that COs describe a complex prison hierarchy that, while being laced with challenges beyond the control of COs, could nevertheless be effectively mitigated through architectural transformation or policy reforms. We highlight the need to consider how prison culture informs and is interpolated through spatial configurations of correctional institutions and how these social and spatial dynamics shape interactions between prisoners.

Scalability Performance Analysis of Blockchain Using Hierarchical Model in Healthcare.

Blockchain technology has become crucial in improving the privacy and security of enterprise applications in the cyber world. However, scalability has become a significant concern for researchers in large organizations, especially those with complex hierarchies and access privileges. As a result, the existing models and consensus algorithms suffer from various issues. Medical centers and healthcare providers are particularly affected by this problem due to the vast amount of data, making it a critical weakness of traditional database management systems. To address this issue, the authors propose a hierarchical model within the Hyperledger Fabric enterprise application, focusing on the healthcare sector as a use case. This model includes multiple organizations at different levels of the hierarchy, such as hospitals, hospital governance, and insurance companies. The initial implementation of this model includes two levels of hierarchy, demonstrating networks of hospitals joining an insurance company. The primary objective of the experiment is to test and improve the network's performance using this model. The model's performance is evaluated by manipulating and scaling environmental factors such as the number of organizations, transaction numbers, channels, block intervals, and block sizes. The benchmarking tool used for this assessment is Hyperledger Caliper, which measures indicators such as success and failure rates, throughput, and latency. Currently, the research focuses only on testing the model's scalability using patient data.