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1.
Adv Neurobiol ; 36: 15-55, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468026

RESUMO

This chapter lays out the elementary principles of fractal geometry underpinning much of the rest of this book. It assumes a minimal mathematical background, defines the key principles and terms in context, and outlines the basics of a fractal analysis method known as box counting and how it is used to perform fractal, lacunarity, and multifractal analyses. As a standalone reference, this chapter grounds the reader to be able to understand, evaluate, and apply essential methods to appreciate and heal the exquisitely detailed fractal geometry of the brain.


Assuntos
Fractais , Humanos
2.
Adv Neurobiol ; 36: 149-172, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468031

RESUMO

Microglia and neurons live physically intertwined, intimately related structurally and functionally in a dynamic relationship in which microglia change continuously over a much shorter timescale than do neurons. Although microglia may unwind and depart from the neurons they attend under certain circumstances, in general, together both contribute to the fractal topology of the brain that defines its computational capabilities. Both neuronal and microglial morphologies are well-described using fractal analysis complementary to more traditional measures. For neurons, the fractal dimension has proved valuable for classifying dendritic branching and other neuronal features relevant to pathology and development. For microglia, fractal geometry has substantially contributed to classifying functional categories, where, in general, the more pathological the biological status, the lower the fractal dimension for individual cells, with some exceptions, including hyper-ramification. This chapter provides a review of the intimate relationships between neurons and microglia, by introducing 2D and 3D fractal analysis methodology and its applications in neuron-microglia function in health and disease.


Assuntos
Fractais , Microglia , Humanos , Neurônios/fisiologia , Encéfalo
3.
Adv Neurobiol ; 36: 795-814, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468064

RESUMO

To explore questions asked in neuroscience, neuroscientists rely heavily on the tools available. One such toolset is ImageJ, open-source, free, biological digital image analysis software. Open-source software has matured alongside of fractal analysis in neuroscience, and today ImageJ is not a niche but a foundation relied on by a substantial number of neuroscientists for work in diverse fields including fractal analysis. This is largely owing to two features of open-source software leveraged in ImageJ and vital to vigorous neuroscience: customizability and collaboration. With those notions in mind, this chapter's aim is threefold: (1) it introduces ImageJ, (2) it outlines ways this software tool has influenced fractal analysis in neuroscience and shaped the questions researchers devote time to, and (3) it reviews a few examples of ways investigators have developed and used ImageJ for pattern extraction in fractal analysis. Throughout this chapter, the focus is on fostering a collaborative and creative mindset for translating knowledge of the fractal geometry of the brain into clinical reality.


Assuntos
Fractais , Pesquisa Translacional Biomédica , Humanos , Processamento de Imagem Assistida por Computador/métodos , Software
4.
Nat Rev Cardiol ; 14(1): 56-64, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27708281

RESUMO

For clinicians grappling with quantifying the complex spatial and temporal patterns of cardiac structure and function (such as myocardial trabeculae, coronary microvascular anatomy, tissue perfusion, myocyte histology, electrical conduction, heart rate, and blood-pressure variability), fractal analysis is a powerful, but still underused, mathematical tool. In this Perspectives article, we explain some fundamental principles of fractal geometry and place it in a familiar medical setting. We summarize studies in the cardiovascular sciences in which fractal methods have successfully been used to investigate disease mechanisms, and suggest potential future clinical roles in cardiac imaging and time series measurements. We believe that clinical researchers can deploy innovative fractal solutions to common cardiac problems that might ultimately translate into advancements for patient care.


Assuntos
Doenças Cardiovasculares/diagnóstico por imagem , Fractais , Técnicas de Imagem Cardíaca/métodos , Doenças Cardiovasculares/patologia , Doenças Cardiovasculares/fisiopatologia , Hemodinâmica/fisiologia , Humanos , Miocárdio/patologia
5.
J Cardiovasc Magn Reson ; 17: 80, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26346700

RESUMO

Many of the structures and parameters that are detected, measured and reported in cardiovascular magnetic resonance (CMR) have at least some properties that are fractal, meaning complex and self-similar at different scales. To date however, there has been little use of fractal geometry in CMR; by comparison, many more applications of fractal analysis have been published in MR imaging of the brain.This review explains the fundamental principles of fractal geometry, places the fractal dimension into a meaningful context within the realms of Euclidean and topological space, and defines its role in digital image processing. It summarises the basic mathematics, highlights strengths and potential limitations of its application to biomedical imaging, shows key current examples and suggests a simple route for its successful clinical implementation by the CMR community.By simplifying some of the more abstract concepts of deterministic fractals, this review invites CMR scientists (clinicians, technologists, physicists) to experiment with fractal analysis as a means of developing the next generation of intelligent quantitative cardiac imaging tools.


Assuntos
Doenças Cardiovasculares/diagnóstico , Sistema Cardiovascular , Fractais , Interpretação de Imagem Assistida por Computador/métodos , Imagem Cinética por Ressonância Magnética/métodos , Modelos Cardiovasculares , Animais , Doenças Cardiovasculares/patologia , Doenças Cardiovasculares/fisiopatologia , Sistema Cardiovascular/patologia , Sistema Cardiovascular/fisiopatologia , Humanos , Valor Preditivo dos Testes , Prognóstico
7.
J Am Coll Nutr ; 21(2): 79-83, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11999546

RESUMO

There is considerable evidence that the war on cancer is not being won. There is, however, strong evidence that a substantial fraction of cancer can be prevented by using existing nutritional knowledge. In this paper we discuss strategies for reducing cancer incidence by implementing this knowledge. The most obvious route for persuading large numbers to change their diets is by individual counseling in a health-care setting, public education campaigns and interventions at the worksite. However, such health promotion actions have met with only limited success. For efforts to change population diets to be successful, a vital component must include changes in govemment policies. Examples of the tools that need to be employed are restrictions on advertising and marketing. Effective action will likely require an economic dimension, namely the employment of taxation and subsidies, for instance, by taxing unhealthy food choices and by subsidizing fruit and vegetables.


Assuntos
Neoplasias/prevenção & controle , Fenômenos Fisiológicos da Nutrição , Governo , Promoção da Saúde , Humanos , Política Nutricional , Papel do Médico
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