En este trabajo se utiliza un método de optimización matemática para resolver el problema selección cartera. Se plantea como programación semi-infinita (PSI). resuelve usando una versión del estocástico aproximaciones externas en MATLAB. El sustituye original por secuencia finita problemas optimización. Los resultados comparan con otras estrategias cartera la desarrollada Markowitz. rea...

The recently reported result from XENON1T experiment indicates that there is an excess with $3.5\sigma$ significance in the electronic recoil events. Interpreted as new physics, sources are needed to account for scattering. We show a dark fermion $\psi$ mass about $ \mathcal{O}\left(10\right)$ MeV semi-annihilation of $Z_3$ matter $X$ and subsequent decay gauge boson $V_\mu$ may be responsible ...

We consider a variety of lattice spin systems (including Ising, Potts and XY models) on $\mathbb{Z}^d$ with long-range interactions the form $J_x = \psi(x) e^{-|x|}$, where $\psi(x) e^{\mathsf{o}(|x|)}$ $|\cdot|$ is an arbitrary norm. characterize explicitly prefactors $\psi$ that give rise to correlation length not analytic in relevant external parameter(s) (inverse temperature $\beta$, magnet...

Using data collected with the CLEO detector operating at the CESR e+e- collider at sqrt[s]=3.97-4.26 GeV, we investigate 15 charmonium decay modes of the psi(4040), psi(4160), and Y(4260) resonances. We confirm, at 11 sigma significance, the BABAR Y(4260)-->pi+pi- J/psi discovery, make the first observation of Y(4260)--> pi(0)pi(0) J/psi (5.1 sigma), and find the first evidence for Y(4260)-->K+...

Using 2.45x10;{7} psi(2S) decays collected with the CLEO-c detector at the Cornell Electron Storage Ring we present the most precise measurements of magnetic dipole transitions in the charmonium system. We measure B(psi(2S)-->gammaeta_{c})=(4.32+/-0.16+/-0.60)x10;{-3}, B(J/psi-->gammaeta_{c})/B(psi(2S)-->gammaeta_{c})=4.59+/-0.23+/-0.64, and B(J/psi-->gammaeta_{c})=(1.98+/-0.09+/-0.30)%. We obs...

It has been indicated that photosystem I (PSI) is susceptible to chilling-light stress in tobacco leaves, but the effect of growth light intensity on chilling-induced PSI photoinhibition in tobacco is unclear. We examined the effects of chilling temperature (4°C) associated with moderate light intensity (300 μmol photons m(-2) s(-1)) on the activities of PSI and photosystem II (PSII) in leaves ...

To investigate the function of the nucleolar protein Nop2p in Saccharomyces cerevisiae, we constructed a strain in which NOP2 is under the control of a repressible promoter. Repression of NOP2 expression lengthens the doubling time of this strain about fivefold and reduces steady-state levels of 60S ribosomal subunits, 80S ribosomes, and polysomes. Levels of 40S subunits increase as the free po...

We developed a novel method for the isolation of the PSI-LHCI-LHCII complex from spinach leaves. The supercomplex was resolved into a core complex (CPI), LHCII trimers, LHCI dimers and LHCII monomers using green gel electrophoresis. We then investigate changes in the fluorescence and absorption spectra of PSI-LHCI-LHCII under high light. In addition, we compared light-induced denaturation of th...