Article
Equal numbers of neuronal and nonneuronal cells make the human brain an isometrically scaledup primate brain.
Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Cidade Universitária, Rio de Janeiro, Brazil.
The Journal of Comparative Neurology (Impact Factor: 3.51). 05/2009; 513(5):53241. DOI: 10.1002/cne.21974 Source: PubMed

Conference Paper: Recapitulation of Recurrence Theory and Practice
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ABSTRACT: In broad strokes this chapter examines the roots of recurrence quantification analysis (RQA) and looks forward into its future. Much has already been written about the theory and application of recurrence methodology to realworld and complex systems. The overarching purpose of this present contribution is to introduce recurrence quantification as a unifying tool that has the timely potential of bringing together numerous and diverse fields of science under a common rubric of dynamical systems. The simple idea is that all scientists are studying "linguistic" systems that possess unique "vocabularies" and varied "grammars." But RQA can cut through these differences and encourage researchers in different research fields and scattered geographical locals to start talking seriously about the similarities of otherwise apparently diverse systems. 1. Context The concept of recurrence has a long mathematical history that can be traced back at least to Poincare (1880) of the late 19 th century and more recently to Feller (1950) of the mid 20 th century. Poincare may be considered the "father" of nonlinear dynamics, whereas Feller was a mathematician focusing on probability theory. As we will see, recurrence analysis is actually a statistical tool that can "diagnose" any moving system, but we are getting ahead of ourselves. Systems can be considered as recurrent if dynamic trajectories describing those systems return exactly to (periodic) or nearby (chaotic) their starting states. According this definition, recurrent systems possess periodicities or quasiperiodicities which keep such systems intact and functioning. Any active system with strong recurrences can be considered to be in some type of steady state or quasisteady state. However, any system exhibiting weak recurrences is either transitioning to another steady state or is moving toward dissolution (cessation). And theoretically, systems possessing no or at best unstructured recurrences are no systems at all in the classical sense, and are better understood as random processes (which nonetheless may have highdimensional structuring that are undetermined as yet). In the second half of the 20 th century three key mathematical breakthroughs (greatly aided by the rise of digital computers) have preceded the inception of modern recurrence quantification analysis (RQA). First, in 1963 Lorenz (1963) (13,559 citations) while modeling weather systems found that small changes in initial conditions in his threevariable system led to unpredictable dynamic outcomes. This modern finding was reminiscent of Newton's threebody problem which Poincare proved had no analytical solution. Thus was born the famous Lorenz strange attractor which digital and analog computers could easily display. Besides displaying sensitivity to initial conditions, strange attractors have return trajectories that are very close but nonexact. Second, in 1981 Takens (1981) (8,206 citations) published results from his work on strange attractors in fluid turbulence. His huge contribution was the mathematical proof that dynamical systems in N dimensions could be reproduced typologicallyThe CISB scientific activity: Recent and seminal achievements., Rome, Italy; 05/2014  [Show abstract] [Hide abstract]
ABSTRACT: The brain is the hub of the human organization. It constitutes about onefiftieth of the body mass and lies within the cranial cavity. Parts are cerebrum, midbrain, pons, medulla oblongata, and cerebellum. Neuro imaging technique is a new promise for brain function and recuperating with cognitive disorders patient. In this tabloid, the execution of a functional Neuro imaging focuses on cognitive disorder that round as a mockup for therapeutic centre. The opposition of the swot up was to asses neurological outputs of sub cortical stimulation and to uses fmri. It is worn to sensory, language, and memory areas in neurosurgical patients with epilepsy. New insights on fundamental processes are brain plasticity is likely to be exposed. 
Article: Sexual dimorphism in the human olfactory bulb: females have more neurons and glial cells than males.
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ABSTRACT: Sex differences in the human olfactory function reportedly exist for olfactory sensitivity, odorant identification and memory, and tasks in which odors are rated based on psychological features such as familiarity, intensity, pleasantness, and others. Which might be the neural bases for these behavioral differences? The number of cells in olfactory regions, and especially the number of neurons, may represent a more accurate indicator of the neural machinery than volume or weight, but besides gross volume measures of the human olfactory bulb, no systematic study of sex differences in the absolute number of cells has yet been undertaken. In this work, we investigate a possible sexual dimorphism in the olfactory bulb, by quantifying postmortem material from 7 men and 11 women (ages 5594 years) with the isotropic fractionator, an unbiased and accurate method to estimate absolute cell numbers in brain regions. Female bulbs weighed 0.132 g in average, while male bulbs weighed 0.137 g, a nonsignificant difference; however, the total number of cells was 16.2 million in females, and 9.2 million in males, a significant difference of 43.2%. The number of neurons in females reached 6.9 million, being no more than 3.5 million in males, a difference of 49.3%. The number of nonneuronal cells also proved higher in women than in men: 9.3 million and 5.7 million, respectively, a significant difference of 38.7%. The same differences remained when corrected for mass. Results demonstrate a sexrelated difference in the absolute number of total, neuronal and nonneuronal cells, favoring women by 4050%. It is conceivable that these differences in quantitative cellularity may have functional impact, albeit difficult to infer how exactly this would be, without knowing the specific circuits cells make. However, the reported advantage of women as compared to men may stimulate future work on sex dimorphism of synaptic microcircuitry in the olfactory bulb.PLoS ONE 11/2014; 9(11):e111733. · 3.53 Impact Factor
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