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    New physics in the charged relativistic Bose gas using zeta-function regularization?

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    The multiplicative anomaly, recently introduced in QFT, plays a fundamental role in solving some mathematical inconsistencies of the widely used zeta-function regularization method. Its physical relevance is still an open question and is here analyzed in the light of a non-perturbative method. Even in this approach the ``different physics'' seems to hold and not to be easily removable by renormalization.Comment: 6 pages, LaTeX. Talk given at the ``SEWM2000 - Strong and Electro-Weak Matter 2000''Conference, June 2000, Marseilles, France. Proceedings to be published by World Scientifi

    Perceptual tuning influences rule generalization: Testing humans with monkey-tailored stimuli

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    Comparative research investigating how nonhuman animals generalize patterns of auditory stimuli often uses sequences of human speech syllables and reports limited generalization abilities in animals. Here, we reverse this logic, testing humans with stimulus sequences tailored to squirrel monkeys. When test stimuli are familiar (human voices), humans succeed in two types of generalization. However, when the same structural rule is instantiated over unfamiliar but perceivable sounds within squirrel monkeys’ optimal hearing frequency range, human participants master only one type of generalization. These findings have methodological implications for the design of comparative experiments, which should be fair towards all tested species’ proclivities and limitations

    Novel role for the LKB1 pathway in controlling monocarboxylate fuel transporters

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    A question preoccupying many researchers is how signal transduction pathways control metabolic processes and energy production. A study by Jang et al. (Jang, C., G. Lee, and J. Chung. 2008. J. Cell Biol. 183:11–17) provides evidence that in Drosophila melanogaster a signaling network controlled by the LKB1 tumor suppressor regulates trafficking of an Sln/dMCT1 monocarboxylate transporter to the plasma membrane. This enables cells to import additional energy sources such as lactate and butyrate, enhancing the repertoire of fuels they can use to power vital activities

    Optimizing the energy with quantum Monte Carlo: A lower numerical scaling for Jastrow-Slater expansions

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    We present an improved formalism for quantum Monte Carlo calculations of energy derivatives and properties (e.g. the interatomic forces), with a multideterminant Jastrow-Slater function. As a function of the number NeN_e of Slater determinants, the numerical scaling of O(Ne)O(N_e) per derivative we have recently reported is here lowered to O(Ne)O(N_e) for the entire set of derivatives. As a function of the number of electrons NN, the scaling to optimize the wave function and the geometry of a molecular system is lowered to O(N3)+O(NNe)O(N^3)+O(N N_e), the same as computing the energy alone in the sampling process. The scaling is demonstrated on linear polyenes up to C60_{60}H62_{62} and the efficiency of the method is illustrated with the structural optimization of butadiene and octatetraene with Jastrow-Slater wave functions comprising as many as 200000 determinants and 60000 parameters
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