An exact master equation for the system-reservoir dynamics under the strong coupling regime and non-Markovian dynamics

In this paper we present a method to derive an exact master equation for a bosonic system coupled to a set of other bosonic systems, which plays the role of the reservoir, under the strong coupling regime, i.e., without resorting to either the rotating-wave or secular approximations. Working with phase-space distribution functions, we verify that the dynamics are separated in the evolution of its center, which follows classical mechanics, and its shape, which becomes distorted. This is the generalization of a result by Glauber, who stated that coherent states remain coherent under certain circumstances, specifically when the rotating-wave approximation and a zero-temperature reservoir are used. We show that the counter-rotating terms generate fluctuations that distort the vacuum state, much the same as thermal fluctuations.Finally, we discuss conditions for non-Markovian dynamics

Phytoseiid mites of Colombia (Acarina: Phytoseiidae).

This is the second report of the phytoseiids of Colombia. A new genus and species, Quadromalus colombiensis and Euseius ricinus n.sp. are described, bringing the total to 17 species of phytoseiids for Colombia

Stellar equilibrium configurations of white dwarfs in the f(R,T)f(R,T) gravity

In this work we investigate the equilibrium configurations of white dwarfs in a modified gravity theory, na\-mely, $f(R,T)$ gravity, for which $R$ and $T$ stand for the Ricci scalar and trace of the energy-momentum tensor, respectively. Considering the functional form $f(R,T)=R+2\lambda T$, with $\lambda$ being a constant, we obtain the hydrostatic equilibrium equation for the theory. Some physical properties of white dwarfs, such as: mass, radius, pressure and energy density, as well as their dependence on the parameter $\lambda$ are derived. More massive and larger white dwarfs are found for negative values of $\lambda$ when it decreases. The equilibrium configurations predict a maximum mass limit for white dwarfs slightly above the Chandrasekhar limit, with larger radii and lower central densities when compared to standard gravity outcomes. The most important effect of $f(R,T)$ theory for massive white dwarfs is the increase of the radius in comparison with GR and also $f(R)$ results. By comparing our results with some observational data of massive white dwarfs we also find a lower limit for $\lambda$, namely, $\lambda >- 3\times 10^{-4}$.Comment: To be published in EPJ

Morphology, biology and pesticide tolerance of Chelotogenes ornatus (Acai: Cheyletidae).

This paper reports on the morphology, biology and pesticide tolerance of Cheletogenes ornatus, the most common predator of Pinnaspis aspidistrae in the region of Juazeiro- Bahia- Brazil. Some differences between C. ornatus from Brazil and redescriptions in the literature are mentioned in this paper. At 28 +ou- 5oC the duration of the life cycle was 40.6 and 31 days for female gametes and male gametes respectively. Females had 2 nymphal stages while the only male obtained in the laboratory had a single nymphal stage. C. ornatus reproduced by thelytokous parthenogenesis, and male gametes were seldom produced. The peak was ca. 0.8 crawler of P. aspidistrae/gemale gamete/day. The least harmful chemicals to adult females of C. ornatus were methyl parathion, malathion, cyhexatin, zineb and sulfur. Those chemicals caused less than 10% mortality of female gametes at he recommended rates on citrus. COncurrently, the first 2 chemicals caused over 70% mortality of crawlers of P. aspidistrae in the laboratory at the recommended rates

Influence of block versus random monomer distribution on the cellular uptake of hydrophilic copolymers

The use of polymers has revolutionized the field of drug delivery in the past two decades. Properties such as polymer size, charge, hydrophilicity, or branching have all been shown to play an important role in the cellular internalization of polymeric systems. In contrast, the fundamental impact of monomer distribution on the resulting biological properties of copolymers remains poorly studied and is always only investigated for biologically active self-assembling polymeric systems. Here, we explore the fundamental influence of monomer distribution on the cellular uptake of nonaggregating and biologically passive copolymers. Reversible addition–fragmentation chain-transfer (RAFT) polymerization was used to prepare precisely defined copolymers of three hydrophilic acrylamide monomers. The cellular internalization of block copolymers was compared with the uptake of a random copolymer where monomers are statistically distributed along the chain. The results demonstrate that monomer distribution in itself has a negligible impact on copolymer uptake