5,345 research outputs found

    Utilizing semantic networks to database and retrieve generalized stochastic colored Petri nets

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    Previous work has introduced the Planning Coordinator (PCOORD), a coordinator functioning within the hierarchy of the Intelligent Machine Mode. Within the structure of the Planning Coordinator resides the Primitive Structure Database (PSDB) functioning to provide the primitive structures utilized by the Planning Coordinator in the establishing of error recovery or on-line path plans. This report further explores the Primitive Structure Database and establishes the potential of utilizing semantic networks as a means of efficiently storing and retrieving the Generalized Stochastic Colored Petri Nets from which the error recovery plans are derived

    Quantifier elimination in C*-algebras

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    The only C*-algebras that admit elimination of quantifiers in continuous logic are C,C2\mathbb{C}, \mathbb{C}^2, C(C(Cantor space)) and M2(C)M_2(\mathbb{C}). We also prove that the theory of C*-algebras does not have model companion and show that the theory of Mn(On+1)M_n(\mathcal {O_{n+1}}) is not āˆ€āˆƒ\forall\exists-axiomatizable for any nā‰„2n\geq 2.Comment: More improvements and bug fixes. To appear in IMR

    Forecasting age-related changes in breast cancer mortality among white and black US women: A functional approach

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    The disparity in breast cancer mortality rates among white and black US women is widening with higher mortality rates among black women. We apply functional time series models on age-specific breast cancer mortality rates for each group of women, and forecast their mortality curves using exponential smoothing state-space models with damping. The data were obtained from the Surveillance, Epidemiology and End Results (SEER) program of the US (SEER, 2007). Mortality data were obtained from the National Centre for Health Statistics (NCHS) available on the SEER*Stat database. We use annual unadjusted breast cancer mortality rates from 1969 to 2004 in 5-year age groups (45-49, 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80-84). Age-specific mortality curves were obtained using nonparametric smoothing methods. The curves are then decomposed using functional principal components and we fit functional time series models with four basis functions for each population separately. The curves from each population are forecast and prediction intervals are calculated. Twenty-year forecasts indicate an over-all decline in future breast cancer mortality rates for both groups of women. This decline is steeper among white women aged 55-73 and black women aged 60-84. For black women under 55 years of age, the forecast rates are relatively stable indicating no significant change in future breast cancer mortality rates among young black women in the next 20 years.Breast cancer mortality, racial and ethnic disparities, screening, trends, forecasting, functional data analysis

    Local solutions in Sobolev spaces with negative indices for the "good" Boussinesq equation

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    We study the local well-posedness of the initial-value problem for the nonlinear "good" Boussinesq equation with data in Sobolev spaces \textit{HsH^s} for negative indices of ss.Comment: Referee comments incorporate

    The Neuroscience of Socioeconomic Status: Correlates, Causes, and Consequences

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    Neuroscience research on socioeconomic status (SES) has begun to characterize aspects of brain structure and function that vary with SES. This review summarizes our current state of knowledge concerning the neural correlates of SES, their likely consequences for human psychology and possible causes of these correlates, including relevant evidence from human and animal research concerning these causes. Challenges of research on the neuroscience of SES are discussed, and the relevance of this topic to neuroscience more generally is considered

    Morality: My brain made me do it

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    The Unknowns of Cognitive Enhancement

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    ā€œMan is not going to wait passively for millions of years before evolution offers him a better brain.ā€ These words are attributed to the 20th century Romanian psychopharmacologist Corneliu Giurgea, an early advocate of cognitive enhancementā€”that is, the use of medications or other brain treatments for improving normal healthy cognition. Contemporary attempts at cognitive enhancement involve an array of drugs and devices for modifying brain function, such as pills taken by students to help them study, or electrical stimulators focused on prefrontal cortex by electronic game players (ā€œe-gamersā€) to sharpen their skills. What is known about current methods of cognitive enhancement? What specifically do they enhance, for whom, and with what risks? We know surprisingly little

    When we enhance cognition with Adderall, do we sacrifice creativity? A preliminary study

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    Rationale: Adderall (mixed amphetamine salts) is used by healthy normal individuals to enhance attention. Research with healthy normal participants and those with attention deficit hyperactivity disorder indicate a possible inverse relationship between attentional function and creativity. This raises the possibility that Adderall could decrease creativity in people using it for cognitive enhancement. Objective: This study was designed to find out whether Adderall impairs creativity in healthy young adults. Material and methods: In a double-blind placebo-controlled study, the effects of Adderall on the performance of 16 healthy young adults were measured on four tests of creativity from the psychological literature: two tasks requiring divergent thought and two requiring convergent thought. Results: Adderall affected performance on the convergent tasks only, in one case enhancing it, particularly for lower performing individuals, and in the other case enhancing it for the lower-performing and impairing it for higher-performing individuals. Conclusion: The preliminary evidence is inconsistent with the hypothesis that Adderall has an overall negative effect on creativity. Its effects on divergent creative thought cannot be inferred with confidence from this study because of the ambiguity of null results. Its effects on convergent creative thought appear to be dependent on the baseline creativity of the individual. Those in the higher range of the normal distribution may be unaffected or impaired, whereas those in the lower range of the normal distribution experience enhancement

    HEMOLYTIC ACTIVITY OF CICER ARIETINUM L. EXTRACTS BY TWO EXTRACTION TECHNIQUES

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    This study were designed to test the efficiency of saponin which extracted from C. arietinum L. by two different extraction techniques as hemolytic agent, one of them carried out by using ultra sonication-Oven assistance extraction (UOAE)with ethanol as extraction solvent of choice while the other technique deals with more than one solvent with longer extraction time Phytochemical analysis of both crude extracts was performed and revealed positive result for saponins, resins, tannins and alkaloids while resins appeared only in liquid-liquid extraction (LLE) meanwhile results showed that flavonoids, terpenes, steroids, glycosides and polyphenols were absent for both crude extracts. Reversed high performance liquid chromatography carried out to detect presence of saponin in these crude extracts. The results of hemolytic effect on human erythrocytes showed that both crude extracts significantly potent as lytic agent compared with synthetic purchased saponin at PĆ¢ā€°Ā¤ 0.05. The highest hemolytic activity was76.27 ƂĀ± 0.18percent at concentration 0.375mg/ml with UOAE technique while the opposite pattern appeared with LLE and the hemolytic activity increase to 79.40 ƂĀ± 0.12percent with the lowest concentration 0.094mg/ml,statistical analysis proved that is saponins involved both of crude extracts which obtained by UOAE and LLE techniques considered as effective hemolytic agent. Ƃ  Keywords: Saponin, Chickpea, Cicer arietinum, Hemolytic activity, Ultra-sonicationƂ&nbsp
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