1,228 research outputs found

    Consciousness and Cosmos: Building an Ontological Framework

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    Contemporary theories of consciousness are based on widely different concepts of its nature, most or all of which probably embody aspects of the truth about it. Starting with a concept of consciousness indicated by the phrase “the feeling of what happens” (the title of a book by Antonio Damásio), we attempt to build a framework capable of supporting and resolving divergent views. We picture consciousness in terms of Reality experiencing itself from the perspective of cognitive agents. Each conscious experience is regarded as composed of momentary feeling events that are combined by recognition and evaluation into extended conscious episodes that bind cognitive contents with a wide range of apparent durations (0.1 secs to 2 or more secs, for us humans, depending on circumstances and context). Three necessary conditions for the existence of consciousness are identified: a) a ground of Reality, envisaged as an universal field of potentiality encompassing all possible manifestations, whether material or 'mental'; b) a transitional zone, leading to; c) a manifest world with its fundamental divisions into material, 'informational' and quale-endowed aspects. We explore ideas about the nature of these necessary conditions, how they may relate to one another and whether our suggestions have empirical implications

    Unsteady transonic small disturbance theory with strong shock waves

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    A theory to correct the transonic small disturbance (TSD) equation to treat strong shock waves in unsteady flow is developed. The technique involves the addition of higher order terms, which are formally of negligible magnitude, to the low frequency TSD equation. These terms are then chosen such that any shock waves in the flow have strengths approximately equal to the appropriate Rankine-Hugoniot shock strength. Two correcting approaches are investigated. The first is to derive a correction for the mean steady flow and then simply use this corrected form for oscillatory flows. The second is to derive a correction for both steady and oscillatory parts of the flow. This second development is the most satisfactory and comparisons of the present results with Euler equation results are generally favorable, particularly regarding shock location, although there are some discrepancies in the pressure distribution in the leading edge region

    Social Security Decisions: Should Recipients Opt for Early Payments?

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    Two Excel-based templates are developed to help determine when it is optimal for starting to receive monthly social security benefits. The decision information accounts for uncertain life expectancy by implementing a rate of return that should be set, at a minimum, to the individual’s expected return on investments or based on a metric provided in the article that considers potential life expectancy. Key Takeaways: Excel templates allow for a comparison of receiving lower monthly social security benefits at an earlier age versus waiting for higher monthly benefits at a later age. A “reserve rule of 72” metric allows for adjustments on comparing the different social security payment structures based on life expectancy. Other adjustments for comparing the different social security structures can made for those who work while receiving benefits

    Intuitive Black-Scholes Option Pricing with a Simple Table

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    The Black-Scholes option pricing model (1973) can be intimidating for the novice. By rearranging and combining some of the variables, one can reduce the number of parameters in the valuation problem from five to two: 1) the option\u27s moneyness ratio and 2) its time-adjusted volatility. This allows the computationally complex Black-Scholes formula to be collapsed into an easy-to-use table similar to those in some popular textbooks. The tabular approach provides an excellent tool for building intuition about the comparative statics in the Black-Scholes equation. Further, the pricing table can be used to price options on dividend-paying stocks, commodities, foreign exchange contracts, futures contracts, and exchanges of assets, and can be inverted to generate implied volatility. Formulas for reproducing the tables in Excel are included

    In vivo tomographic imaging based on bioluminescence

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    The most important task for bioluminescence imaging is to identify the emission source from the captured bioluminescent signal on the surface of a small tested animal. Quantitative information on the source location, geometry and intensity serves for in-vivo monitoring of infectious diseases, tumor growth, metastases in the small animal. In this paper, we present a point-spread function-based method for reconstructing the internal bioluminescent source from the surface light output flux signal. The method is evaluated for sensing the internal emission sources in nylon phantoms and within a live mouse. The surface bioluminescent signal is taken with a highly sensitive CCD camera. The results show the feasibility and efficiency of the proposed point-spread function-based method

    On the abundance of non-cometary HCN on Jupiter

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    Using one-dimensional thermochemical/photochemical kinetics and transport models, we examine the chemistry of nitrogen-bearing species in the Jovian troposphere in an attempt to explain the low observational upper limit for HCN. We track the dominant mechanisms for interconversion of N2-NH3 and HCN-NH3 in the deep, hightemperature troposphere and predict the rate-limiting step for the quenching of HCN at cooler tropospheric altitudes. Consistent with other investigations that were based solely on time-scale arguments, our models suggest that transport-induced quenching of thermochemically derived HCN leads to very small predicted mole fractions of hydrogen cyanide in Jupiter's upper troposphere. By the same token, photochemical production of HCN is ineffective in Jupiter's troposphere: CH4-NH3 coupling is inhibited by the physical separation of the CH4 photolysis region in the upper stratosphere from the NH3 photolysis and condensation region in the troposphere, and C2H2-NH3 coupling is inhibited by the low tropospheric abundance of C2H2. The upper limits from infrared and submillimeter observations can be used to place constraints on the production of HCN and other species from lightning and thundershock sources.Comment: 56 pages, 0 tables, 6 figures. Submitted to Faraday Discussions [in press

    Results from the Atacama B-mode Search (ABS) Experiment

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    The Atacama B-mode Search (ABS) is an experiment designed to measure cosmic microwave background (CMB) polarization at large angular scales (>40\ell>40). It operated from the ACT site at 5190~m elevation in northern Chile at 145 GHz with a net sensitivity (NEQ) of 41 μ\muKs\sqrt{\rm s}. It employed an ambient-temperature sapphire half-wave plate rotating at 2.55 Hz to modulate the incident polarization signal and reduce systematic effects. We report here on the analysis of data from a 2400 deg2^2 patch of sky centered at declination 42-42^\circ and right ascension 2525^\circ. We perform a blind analysis. After unblinding, we find agreement with the Planck TE and EE measurements on the same region of sky. We marginally detect polarized dust emission and give an upper limit on the tensor-to-scalar ratio of r<2.3r<2.3 (95% cl) with the equivalent of 100 on-sky days of observation. We also present a new measurement of the polarization of Tau A and introduce new methods associated with HWP-based observations.Comment: 38 pages, 11 figure

    Síndrome de Stevens-Johnson. Apresentação de Caso Clínico

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    Introdução: A Síndrome de Stevens-Johnson (SSJ) é uma doença mucocutânea rara e potencialmente fatal, mais frequente no sexo masculino, cuja incidência aumenta com a idade e em determinados grupos de risco. A SSJ e a Necrólise Tóxica Epidérmica (NET) são duas entidades da mesma doença, com severidade diferente. A etiologia não é clara, mas pensa-se que se deva maioritariamente a reacções adversas a fármacos. Caso clínico: Um jovem de 17 anos de idade, sem antecedentes pessoais relevantes, foi observado no Serviço de Urgência por surgimento de lesões maculopapulares, com 3 dias de evolução, dispersas pela face, cavidade oral, tronco e extremidades, com prostração e taquicardia. Foi internado com o diagnóstico de SSJ. Discussão e Conclusões: O SSJ e a NET têm grande morbilidade e considerável mortalidade. O rápido reconhecimento desta identidade, com a remoção do fármaco desencadeador é essencial. A perda da função de barreira da pele, com a consequente alteração da homeostasia, implica muitas vezes a manutenção da terapêutica de suporte em Unidades de Cuidados Intensivos ou de Queimados.info:eu-repo/semantics/publishedVersio
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