RESUMEN
Functional magnetic resonance imaging (fMRI) provides insights into cognitive processes with significant clinical potential. However, delays in brain region communication and dynamic variations are often overlooked in functional network studies. We demonstrate that networks extracted from fMRI cross-correlation matrices, considering time lags between signals, show remarkable reliability when focusing on statistical distributions of network properties. This reveals a robust brain functional connectivity pattern, featuring a sparse backbone of strong 0-lag correlations and weaker links capturing coordination at various time delays. This dynamic yet stable network architecture is consistent across rats, marmosets, and humans, as well as in electroencephalogram (EEG) data, indicating potential universality in brain dynamics. Second-order properties of the dynamic functional network reveal a remarkably stable hierarchy of functional correlations in both group-level comparisons and test-retest analyses. Validation using alcohol use disorder fMRI data uncovers broader shifts in network properties than previously reported, demonstrating the potential of this method for identifying disease biomarkers.
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Encéfalo , Electroencefalografía , Imagen por Resonancia Magnética , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Animales , Humanos , Ratas , Electroencefalografía/métodos , Masculino , Red Nerviosa/fisiología , Red Nerviosa/diagnóstico por imagen , Mapeo Encefálico/métodos , Callithrix/fisiología , AdultoRESUMEN
Radical cystectomy is the gold standard treatment in localized muscle-invasive bladder cancer according to today's guidelines. However, in many cases, surgery is not possible due to the patient's general condition, or the patient refuses bladder removal. In such cases, as well as in some selected patients suitable for surgery, trimodal organ preservation therapy is an alternative, which provides the patient with similar survival, local tumor control, so that 80% of patients retain their bladder. In some cases, due to complications or a muscle-invasive local recurrence in the bladder, the bladder may not be retained. At this point, a salvage cystectomy can still save the patient's quality of life and life. Adequate patient selection is a prerequisite for effective trimodal therapy. We summarize the components of organ-preserving treatment, including radiation therapy, its state-of-the-art technology, results and side effects. The results and toxicity of trimodal treatment are compared with those of radical cystectomy.
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Neoplasias de la Vejiga Urinaria , Terapia Combinada , Humanos , Músculos , Invasividad Neoplásica , Calidad de Vida , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/terapiaRESUMEN
The Internet on the router level, is a complex network embedded in a geographical space. We provide experimental evidences suggesting that the average travel time for a message, with fixed length, increases roughly as the square root of the geographical distance. To understand this scaling law and other measurable topological properties of the Internet as a graph, we introduce and study a simple network model. The model is based on a few realistic socio-economic facts/assumptions and qualitatively reproduces the experimentally observed stylized facts.
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The distribution of scientific citations for publications selected with different rules (author, topic, institution, country, journal, etc ) collapse on a single curve if one plots the citations relative to their mean value. We find that the distribution of "shares" for the Facebook posts rescale in the same manner to the very same curve with scientific citations. This finding suggests that citations are subjected to the same growth mechanism with Facebook popularity measures, being influenced by a statistically similar social environment and selection mechanism. In a simple master-equation approach the exponential growth of the number of publications and a preferential selection mechanism leads to a Tsallis-Pareto distribution offering an excellent description for the observed statistics. Based on our model and on the data derived from PubMed we predict that according to the present trend the average citations per scientific publications exponentially relaxes to about 4.
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Internet/estadística & datos numéricos , Ciencia/estadística & datos numéricos , Medios de Comunicación Sociales/estadística & datos numéricos , Red Social , Algoritmos , Bibliometría , Humanos , Difusión de la Información/métodos , Internet/tendencias , Factor de Impacto de la Revista , Modelos Teóricos , PubMed/estadística & datos numéricos , PubMed/tendencias , Publicaciones/estadística & datos numéricos , Publicaciones/tendencias , Ciencia/tendencias , Medios de Comunicación Sociales/tendenciasRESUMEN
Given a network, the statistical ensemble of its graph-Voronoi diagrams with randomly chosen cell centers exhibits properties convertible into information on the network's large scale structures. We define a node-pair level measure called Voronoi cohesion which describes the probability for sharing the same Voronoi cell, when randomly choosing g centers in the network. This measure provides information based on the global context (the network in its entirety), a type of information that is not carried by other similarity measures. We explore the mathematical background of this phenomenon and several of its potential applications. A special focus is laid on the possibilities and limitations pertaining to the exploitation of the phenomenon for community detection purposes.
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We have studied invasion processes in two-strategy evolutionary games on a square lattice for imitation rule when the players interact with their nearest neighbors. Monte Carlo simulations are performed for systems where the pair interactions are composed of a unit strength coordination game when varying the strengths of the self-dependent and cross-dependent components at a fixed noise level. The visualization of strategy distributions has clearly indicated that circular homogeneous domains evolve into squares with an orientation dependent on the composition. This phenomenon is related to the anisotropy of invasion velocities along the interfaces separating the two homogeneous regions. The quantified invasion velocities indicate the existence of a parameter region in which the invasions are opposite for the horizontal (or vertical) and the tilted interfaces. In this parameter region faceted islands of both strategies shrink and the system evolves from a random initial state into the homogeneous state that first percolated.
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The average travelling speed increases in a nontrivial manner with the travel distance. This leads to scaling-like relations on quite extended spatial scales, for all mobility modes taken together and also for a given mobility mode in part. We offer a wide range of experimental results, investigating and quantifying this universal effect and its measurable causes. The increasing travelling speed with the travel distance arises from the combined effects of: choosing the most appropriate travelling mode; the structure of the travel networks; the travel times lost in the main hubs, starting or target cities; and the speed limit of roads and vehicles.
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Viaje , Toma de Decisiones , Sistemas de Información Geográfica , Humanos , Hungría , Conceptos Matemáticos , Modelos Teóricos , Factores de Tiempo , Transportes/métodos , Viaje/psicología , Estados UnidosRESUMEN
We study a three-strategy spatial evolutionary prisoner's dilemma game with imitation and logit update rules. Players can follow the always-cooperating, always-defecting or the win-stay-lose-shift (WSLS) strategies and gain their payoff from games with their direct neighbors on a square lattice. The friendliness parameter of the WSLS strategy-characterizing its cooperation probability in the first round-tunes the cyclic component of the game determining whether the game can be characterized by a potential. We measured and calculated the phase diagrams of the system for a wide range of parameters. When the game is a potential game and the logit rule is applied, the theoretically predicted phase diagram agrees very well with the simulation results. Surprisingly, this phase diagram can be accurate even in the nonpotential case if there are only two surviving strategies in the stationary state; this result harmonizes with the fact that all 2×2 games are potential games. For the imitation dynamics, we found that the effects of spatiality combined with the presence of two cooperative strategies are so strong that they suppress even substantial changes in the payoff matrix, thus the phase diagrams are independent of the cyclic component's intensity. At the same time, this type of strategy update mechanism supports the formation of cooperative clusters that results in a cooperative society in a wider parameter range compared to the logit dynamics.
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Modelos Teóricos , Dilema del Prisionero , Simulación por Computador , Conducta CooperativaRESUMEN
INTRODUCTION: Mosaic trisomy 8 syndrome shows significant phenotypic variability. High forehead, deep set eyes, wide base of the nose, upturned tip of the nose, protruding lips, prominent ears, strabism, corpus callosum agenesia, deep plantar furrow and variable degree of psychomotor retardation are present in most patients. PATIENTS/METHODS: The authors describe a patient with severe motor and mental retardation, optic disc hypoplasia, cardiomyopathy and partial extrahepatic bile-duct atresia, who's mother was treated for toxoplasma infection in her pregnancy. Perinatal infection of the child was ruled out by the documentation of decreasing IgG values in the mother and newborn and normal IgM levels in the newborn. RESULTS: Facial characteristics and the bilateral deep plantar furrow raised the possibility of trisomy 8 syndrome. Routine chromosomal analysis and fluorescent in situ hybridization studies revealed a normal cell line, mosaic trisomy 8 in 13% of the cells, and a pericentric marker 8 ring chromosome in 27% of the cells. CONCLUSION: The authors suggest that the periconceptional toxoplasma infection may play a role in the occurrence of the mosaic trisomy presenting with cardiomyopathy and partial bile-duct atresia previously undescribed in this syndrome.
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Cromosomas Humanos Par 8 , Mosaicismo , Complicaciones Parasitarias del Embarazo , Toxoplasmosis/complicaciones , Trisomía , Conductos Biliares/patología , Cardiomiopatías/parasitología , Femenino , Humanos , Embarazo , Síndrome , Trisomía/genéticaRESUMEN
We study a spatial evolutionary rock-paper-scissors game with synchronized strategy updating. Players gain their payoff from games with their four neighbors on a square lattice and can update their strategies simultaneously according to the logit rule, which is the noisy version of the best-response dynamics. For the synchronized strategy update two types of global oscillations (with an ordered strategy arrangement and periods of three and six generations) can occur in this system in the zero noise limit. At low noise values, all nine oscillating phases are present in the system by forming a self-organizing spatial pattern due to the comprising invasion and speciation processes along the interfaces separating the different domains.
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Evolutionary games are studied here with two types of players located on a chessboard or on a bipartite random regular graph. Each player's income comes from matching-pennies games played with the four neighbors. The players can modify their own strategies according to a myopic strategy update resembling the Glauber dynamics for the kinetic Ising model. This dynamical rule drives the system into a stationary state where the two strategies are present with the same probability without correlations between the nearest neighbors while a weak correlation is induced between the second and the third neighbors. In stationary states, the deviation from the detailed balance is quantified by the evaluation of entropy production. Finally, our analysis is extended to evolutionary games where the uniform pair interactions are composed of an anticoordination game and a weak matching-pennies game. This system preserves the Ising type order-disorder transitions at a critical noise level decreasing with the strength of the matching-pennies component for both networks.