Density-dependent hopping for ultracold atoms immersed in a Bose-Einstein-condensate vortex lattice

Both mixtures of atomic Bose-Einstein condensates and systems with atoms trapped in optical lattices have been intensely explored theoretically, mainly due to the exceptional developments on the experimental side. We investigate the properties of ultracold atomic impurities (bosons) immersed in a vortex lattice of a second Bose-condensed species. In contrast to the static optical-lattice configuration, the vortex lattice presents intrinsic dynamics given by its Tkachenko modes. These excitations induce additional correlations between the impurities, which consist in a long-range attractive potential and in a density-dependent hopping, described here in the framework of an extended Bose-Hubbard model. We compute the quantum phase diagram of the impurity species through a Gutzwiller ansatz and through the mean-field approach, and separately identify the effects of the two additional terms, i.e., the shift and the deformation of the Mott insulator lobes. The long-range attraction, in particular, induces the existence of a triple point in the phase diagram, in agreement with previous quantum Monte Carlo calculations [Chaviguri \emph{et al.}, Phys. Rev. A \textbf{95}, 053639 (2017)].Comment: 8 pages, 4 figure

Distribution of Deroceras reticulatum (Müller, 1774) (Pulmonata Stylommatophora) in Argentina with first record of the Reserva de Usos Múltiples Isla Martin Garcia, Río de la Plata superior

Deroceras reticulatum is a misanthropic European species spread widely throughout South America. At the moment this species is considered a ‘pest’ in direct sowing such as maize, soybean, sunflower, wheat, alfalfa and clovers, among others. The aim of this paper is to report the first record of D. reticulatum in the Reserva de Usos Multiples Isla Martín García, Buenos Aires province and to provide information about this species distribution in five Argentina provinces.Deroceras reticulatum é uma espécie sinantrópica oriunda da Europa e com grande dispersão na América do Sul. Esta espécie é considerada atualmente praga dos cultivos de semeadura direta de milho, soja, trigo, girassol, alfafa e trevos, entre outros. O presente trabalho tem por objetivo comunicar o primeiro achado do agriolimácido D. reticulatum na Reserva de usos múltiplos Ilha Martín García, província de Buenos Aires e proporcionar informação sobre a distribuição desta espécie em cinco províncias argentinas

On the evolution of decoys in plant immune systems

The Guard-Guardee model for plant immunity describes how resistance proteins (guards) in host cells monitor host target proteins (guardees) that are manipulated by pathogen effector proteins. A recently suggested extension of this model includes decoys, which are duplicated copies of guardee proteins, and which have the sole function to attract the effector and, when modified by the effector, trigger the plant immune response. Here we present a proof-of-principle model for the functioning of decoys in plant immunity, quantitatively developing this experimentally-derived concept. Our model links the basic cellular chemistry to the outcomes of pathogen infection and resulting fitness costs for the host. In particular, the model allows identification of conditions under which it is optimal for decoys to act as triggers for the plant immune response, and of conditions under which it is optimal for decoys to act as sinks that bind the pathogen effectors but do not trigger an immune response.Comment: 15 pages, 6 figure

A quantum mechanical insight into SN2 reactions: Semiclassical initial value representation calculations of vibrational features of the Cl−^---CH3_3Cl pre-reaction complex with the VENUS suite of codes

The role of vibrational excitation of reactants in driving reactions involving polyatomic species has been often studied by means of classical or quasi-classical trajectory simulations. We propose a different approach based on investigation of vibrational features of the Cl$^-$--CH$_3$Cl pre-reaction complex for the Cl$^-$ + CH$_3$Cl SN$_2$ reaction. We present vibrational power spectra and frequency estimates for the title pre-reaction complex calculated at the level of classical, semiclassical, and second-order vibrational perturbation theory on a pre-existing analytical potential energy surface. The main goals of the paper are the study of anharmonic effects and understanding of vibrational couplings that permit energy transfer between the collisional kinetic energy and the internal vibrations of the reactants. We provide both classical and quantum pictures of intermode couplings and show that the SN2 mechanism is favored by the coupling of a C--Cl bend involving the Cl$^-$ projectile with the CH$_3$ rocking motion of the target molecule. We also illustrate how the routines needed for semiclassical vibrational spectroscopy simulations can be interfaced in a user-friendly way to pre-existing molecular dynamics software. In particular, we present an implementation of semiclassical spectroscopy into the VENUS suite of codes, thus providing a useful computational tool for users who are not experts of semiclassical dynamics

IL-17 polarization of MAIT cells is derived from the activation of two different pathways

MAIT cells are expanded in salivary glands of patients with Sjogren's syndrome and are IL-17 polarized. IL-7 and IL-23 induce IL-17 production activating two different pathways: IL-7 stimulation induces in fact a significant STAT3 and HIF1alpha upregulation, conversely, IL-23 stimulation significantly induces RORc overexpression in MAIT cells of patients with Sjogren's syndrome

Phase transitions in the Potts spin glass model

We have studied the Potts spin glass with 2-state Ising spins and s-state Potts variables using a cluster Monte Carlo dynamics. The model recovers the +- J Ising spin glass (SG) for s=1 and exhibits for all s a SG transition at T_{SG}(s) and a percolation transition at higher temperature T_p(s). We have shown that for all values of $s\neq 1$ at T_p(s) there is a thermodynamical transition in the universality class of a ferromagnetic s-state Potts model. The efficiency of the cluster dynamics is compared with that of standard spin flip dynamics.Comment: 8 pages, Latex, with 8 EPS fig

Spectrally resolved observations of atmospheric emitted radiance in the H2O rotation band

This paper presents the project Earth Cooling by Water Vapor Radiation, an observational programme, which aims at developing a database of spectrally resolved far infrared observations, in atmospheric dry conditions, in order to validate radiative transfer models and test the quality of water vapor continuum and line parameters. The project provides the very first set of far-infrared spectral downwelling radiance measurements, in dry atmospheric conditions, which are complemented with Raman Lidar-derived temperature and water vapor profiles