Analysis of Ωc∗(css)\Omega_c^*(css) and Ωb∗(bss)\Omega_b^*(bss) with QCD sum rules

In this article, we calculate the masses and residues of the heavy baryons $\Omega_c^*(css)$ and $\Omega_b^*(bss)$ with spin-parity ${3/2}^+$ with the QCD sum rules. The numerical values are compatible with experimental data and other theoretical estimations.Comment: 13 pages, 8 figures, slight versio

High quality GaMnAs films grown with As dimers

We demonstrate that GaMnAs films grown with As2 have excellent structural, electrical and magnetic properties, comparable or better than similar films grown with As4. Using As2, a Curie temperature of 112K has been achieved, which is slightly higher than the best reported to date. More significantly, films showing metallic conduction have been obtained over a much wider range of Mn concentrations (from 1.5% to 8%) than has been reported for films grown with As4. The improved properties of the films grown with As2 are related to the lower concentration of antisite defects at the low growth temperatures employed.Comment: 8 pages, accepted for publication in J. Crystal Growt

The transition form factors for semi-leptonic weak decays of J/ψJ/\psi in QCD sum rules

Within the Standard Model, we investigate the semi-leptonic weak decays of $J/\psi$. The various form factors of $J/\psi$ transiting to a single charmed meson ($D^{(*)}_{(d,s)}$) are studied in the framework of the QCD sum rules. These form factors fully determine the rates of the weak semi-leptonic decays of $J/\psi$ and provide valuable information about the non-perturbative QCD effects. Our results indicate that the decay rate of the semi-leptonic weak decay mode $J/\psi \to D^{(*)-}_{s}+e^{+}+\nu_{e}$ is at order of $10^{-10}$.Comment: 28 pages, 6 figures, revised version to be published in Eur.Phys.J.

Design of fluorinated cyclopropane derivatives of 2-phenylcyclopropylmethylamine leading to identification of a selective serotonin 2C (5-HT2C) receptor agonist without 5-HT2B agonism

A new series of fluorinated 5-HT2C agonists were designed and synthesized on the basis of our previous work on 2-phenylcyclopropylmethylamines as a potential approach for the treatment of central nervous system disorders. Key fluorinated cyclopropane moieties were constructed through transition metal catalyzed [2 + 1]-cycloaddition of aromatic vinyl fluorides, and the absolute stereochemistry of the representative compound (–)-21a was established. Functional activity measuring calcium flux at 5-HT2 receptors reveals high potency for compounds (+)-21a-d. In particular, (+)-21b had no detectable 5-HT2B agonism and displayed reasonable selectivity against 5-HT2A. Molecular docking studies were further performed to explain the compounds’ possible binding poses to the 5-HT2C receptor. © 201

Analysis of the Y(4140) and related molecular states with QCD sum rules

In this article, we assume that there exist scalar ${D}^\ast {\bar {D}}^\ast$, ${D}_s^\ast {\bar {D}}_s^\ast$, ${B}^\ast {\bar {B}}^\ast$ and ${B}_s^\ast {\bar {B}}_s^\ast$ molecular states, and study their masses using the QCD sum rules. The numerical results indicate that the masses are about $(250-500) \rm{MeV}$ above the corresponding ${D}^\ast -{\bar {D}}^\ast$, ${D}_s^\ast -{\bar {D}}_s^\ast$, ${B}^\ast -{\bar {B}}^\ast$ and ${B}_s^\ast -{\bar {B}}_s^\ast$ thresholds, the Y(4140) is unlikely a scalar ${D}_s^\ast {\bar {D}}_s^\ast$ molecular state. The scalar $D^\ast {\bar D}^\ast$, $D_s^\ast {\bar D}_s^\ast$, $B^\ast {\bar B}^\ast$ and $B_s^\ast {\bar B}_s^\ast$ molecular states maybe not exist, while the scalar ${D'}^\ast {\bar {D'}}^\ast$, ${D'}_s^\ast {\bar {D'}}_s^\ast$, ${B'}^\ast {\bar {B'}}^\ast$ and ${B'}_s^\ast {\bar {B'}}_s^\ast$ molecular states maybe exist.Comment: 19 pages, 36 figures, slight revisio

Design and Discovery of Functionally Selective Serotonin 2C (5-HT2C) Receptor Agonists

On the basis of the structural similarity of our previous 5-HT2C agonists with the melatonin receptor agonist tasimelteon and the putative biological cross-talk between serotonergic and melatonergic systems, a series of new (2,3-dihydro)benzofuran-based compounds were designed and synthesized. The compounds were evaluated for their selectivity toward 5-HT2A, 5-HT2B, and 5-HT2C receptors in the calcium flux assay with the ultimate goal to generate selective 5-HT2C agonists. Selected compounds were studied for their functional selectivity by comparing their transduction efficiency at the G protein signaling pathway versus β-arrestin recruitment. The most functionally selective compound (+)-7e produced weak β-arrestin recruitment and also demonstrated less receptor desensitization compared to serotonin in both calcium flux and phosphoinositide (PI) hydrolysis assays. We report for the first time that selective 5-HT2C agonists possessing weak β-arrestin recruitment can produce distinct receptor desensitization properties. © 2016 American Chemical Society

JAZ8 Interacts with VirE3 attenuating agrobacterium mediated root tumorigenesis

Agrobacterium tumefaciens can cause crown gall tumors by transferring both an oncogenic piece of DNA (T-DNA) and several effector proteins into a wide range of host plants. For the translocated effector VirE3 multiple functions have been reported. It acts as a transcription factor in the nucleus binding to the Arabidopsis thaliana pBrp TFIIB-like protein to activate the expression of VBF, an F-box protein involved in degradation of the VirE2 and VIP1 proteins, facilitating Agrobacterium-mediated transformation. Also VirE3 has been found at the plasma membrane, where it could interact with VirE2. Here, we identified AtJAZ8 in a yeast two-hybrid screening with VirE3 as a bait and confirmed the interaction by pull-down and bimolecular fluorescence complementation assays. We also found that the deletion of virE3 reduced Agrobacterium virulence in a root tumor assay. Overexpression of virE3 in Arabidopsis enhanced tumorigenesis, whereas overexpression of AtJAZ8 in Arabidopsis significantly decreased the numbers of tumors formed. Further experiments demonstrated that AtJAZ8 inhibited the activity of VirE3 as a plant transcriptional regulator, and overexpression of AtJAZ8 in Arabidopsis activated AtPR1 gene expression while it repressed the expression of AtPDF1.2. Conversely, overexpression of virE3 in Arabidopsis suppressed the expression of AtPR1 whereas activated the expression of AtPDF1.2. Our results proposed a novel mechanism of counter defense signaling pathways used by Agrobacterium, suggesting that VirE3 and JAZ8 may antagonistically modulate the salicylic acid/jasmonic acid (SA/JA)-mediated plant defense signaling response during Agrobacterium infection.Plant science

Analysis of the vertexes ΞQ∗ΞQ′V\Xi_Q^*\Xi'_Q V, ΣQ∗ΣQV\Sigma_Q^*\Sigma_Q V and radiative decays ΞQ∗→ΞQ′γ\Xi_Q^*\to \Xi'_Q \gamma, ΣQ∗→ΣQγ\Sigma_Q^*\to \Sigma_Q \gamma

In this article, we study the vertexes $\Xi_Q^*\Xi'_Q V$ and $\Sigma_Q^* \Sigma_Q V$ with the light-cone QCD sum rules, then assume the vector meson dominance of the intermediate $\phi(1020)$, $\rho(770)$ and $\omega(782)$, and calculate the radiative decays $\Xi_Q^*\to \Xi'_Q \gamma$ and $\Sigma_Q^*\to \Sigma_Q \gamma$.Comment: 28 pages, 4 tables, revised versio

Environment-Induced Decoherence and the Transition From Quantum to Classical

We study dynamics of quantum open systems, paying special attention to those aspects of their evolution which are relevant to the transition from quantum to classical. We begin with a discussion of the conditional dynamics of simple systems. The resulting models are straightforward but suffice to illustrate basic physical ideas behind quantum measurements and decoherence. To discuss decoherence and environment-induced superselection einselection in a more general setting, we sketch perturbative as well as exact derivations of several master equations valid for various systems. Using these equations we study einselection employing the general strategy of the predictability sieve. Assumptions that are usually made in the discussion of decoherence are critically reexamined along with the ``standard lore'' to which they lead. Restoration of quantum-classical correspondence in systems that are classically chaotic is discussed. The dynamical second law -it is shown- can be traced to the same phenomena that allow for the restoration of the correspondence principle in decohering chaotic systems (where it is otherwise lost on a very short time-scale). Quantum error correction is discussed as an example of an anti-decoherence strategy. Implications of decoherence and einselection for the interpretation of quantum theory are briefly pointed out.Comment: 80 pages, 7 figures included, Lectures given by both authors at the 72nd Les Houches Summer School on "Coherent Matter Waves", July-August 199