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Wolf diet in an agricultural landscape of north-eastern Turkey
No full textIn this study, we investigated wolf feeding ecology in Kars province, north-eastern Turkey, by analysing 72 scat samples collected in spring 2013. Ongoing camera trap surveys suggest that large wild ungulates are exceptionally rare in the region. On the contrary, livestock is abundant. Accordingly, scats analysis revealed that livestock constituted most of the biomass intake for wolves, although small mammals were the most frequent prey items. Wild ungulates were occasional prey, and although wolves make use of the main village garbage dump as a food source, garbage remains were scarce in scat samples. Wolf dependence on anthropogenic resources, primarily livestock, generates human-wildlife conflicts in the study area. Uncontrolled carcass disposal seems to boost this wolf behaviour. Synanthropy enhances the probability of wolf-human encounters and thus increases the risk of direct persecution, vehicle collisions, and hybridisation with dogs. When livestock is not available, small mammals are an important alternative prey for wolves. This may increase interspecific competition, particularly with lynx, which is also lacking natural prey in the area. Our preliminary results contribute to wolf ecology and conservation in the Anatolian-Caucasian range, where further studies are urgently needed to generate baseline data
The effect of electron and ion temperature on the refractive index surface of 1-10 kHz whistler mode waves in the innermagnetosphere
No full textWhistler mode waves in the magnetosphere play an important role in the energy dynamics of the Earth's radiation belts. Previous theoretical work has been extended to include ions in the fully adiabatic warm plasma theory. Using a finite electron and ion temperature of 1 eV, refractive index surfaces are calculated for 1-10 kHz whistler mode waves in the inner magnetosphere (L less than or similar to 2.5). For the frequencies of interest, a finite ion temperature is found to have a greater effect on the refractive index surface than the electron temperature and the primary effect is to close an otherwise open refractive index surface. Including a finite ion temperature is especially important when the wave frequency is just above the local lower hybrid resonance frequency. For wave frequencies more than approximate to 1 kHz above the local lower hybrid resonance frequency, including the ion temperature has a negligible effect on the refractive index surface calculation. The results are used to assess previous conclusions on whether in situ whistler mode sources can be realistically used to precipitate energetic electrons. It is found that the number of in situ sources needed to illuminate the inner plasmasphere (L less than or similar to 2.5) with whistler mode energy may be greater than previously predicted
Anti-inflammatory modulation of microglia via CD163-targeted glucocorticoids protects dopaminergic neurons in the 6-OHDA Parkinson's disease model
No full textIncreasing evidence supports a decisive role for inflammation in the neurodegenerative process of Parkinson's disease (PD). The immune response in PD seems to involve, not only microglia, but also other immune cells infiltrated into the brain. Indeed, we observed here the infiltration of macrophages, specifically CD163+ macrophages, into the area of neurodegeneration in the 6-hydroxydopamine (6-OHDA) PD model. Therefore, we investigated the therapeutic potential of the infiltrated CD163+ macrophages to modulate local microglia in the brain to achieve neuroprotection. To do so, we designed liposomes targeted for the CD163 receptor to deliver dexamethasone (Dexa) into the CD163+ macrophages in the 6-OHDA PD model. Our data show that a fraction of the CD163-targeted liposomes were carried into the brain after peripheral intravenous injection. The 6-OHDA-lesioned rats that received repeated intravenous CD163-targeted liposomes with Dexa for 3 weeks exhibited better motor performance than the control groups and had minimal glucocorticoid-driven side effects. Furthermore, these animals showed better survival of dopaminergic neurons in substantia nigra and an increased number of microglia expressing major histocompatibility complex II. Therefore, rats receiving CD163-targeted liposomes with Dexa were partially protected against 6-OHDA-induced dopaminergic neurodegeneration, which correlated with a distinctive microglia response. Altogether, our data support the use of macrophages for the modulation of brain neurodegeneration and specifically highlight the potential of CD163-targeted liposomes as a therapeutic tool in PD
Tunable WGM resonators from optically trapped dye doped liquid crystal emulsion droplets
No full textWe have built a complex apparatus for optical trapping, stretching, heating and concurrent whispering gallery mode (WGM) lasing excitation of liquid crystal (LC) emulsion micro-droplets doped with various fluorescent dyes. We have explored the changes of WGM lasing wavelength when the LC droplets were optically stretched or electrically heated beyond the transition to the isotropic phase. We have found that the range of lasing wavelengths was in some cases considerably higher than when we optically stretched ordinary fluorescent oil droplets in our previous experiments
Refractive index-enhanced vortex lattices
No full textLight propagation through vortex matter in atomic Bose-Einstein condensates is examined. It is shown that vortex matter can be used as a photonic crystal by a refractive index enhancement scheme. Band structure of the vortex lattice is numerically calculated. Index enhanced vortex matter is shown to exhibit large refractive index contrast with the dilute thermal gas background in the vortex core. Depending on the depth of the index contrast full or directional photonic band gaps are found in the band structure. Experimental parameters required to generate band gaps in the visible region of the electromagnetic spectrum are calculated
Electromagnetically induced left-handedness in a dense gas of three-level atoms
No full textWe discuss how a three-level system can be used to change the frequency-dependent magnetic permeability of an atomic gas to be significantly different from 1. We derive the conditions for such a scheme to be successful and briefly discuss the resulting macroscopic electrodynamics. We find that it may be possible to obtain left-handed electrodynamics for an atomic gas using three atomic levels
Motional macroscopic quantum superposition states of a trapped three-level ion
No full textWe investigate quantum dynamical properties of a trapped three-level ion interacting with two laser beams in Lambda configuration. A unitary transformation method is developed to study the interaction of the ion with its vibrational phonons, quanta of ion's own center-of-mass motion. Under certain conditions on laser parameters, this interaction is shown to be unitarily equivalent to two-phonon cascade transitions. Complicated temporal behaviors of level populations and mean number of phonons are described clearly by identifying dynamical variables of the cascade model as building blocks. Furthermore, analyzing quantum states of vibrational phonons by Husimi-Q function, we find that at times, determined by the underlying cascade dynamics, two- and three-component macroscopic quantum superposition states can be obtained depending on the Lamb-Dicke parameter and the initial conditions of the system. A wide range of initial conditions and experimental parameters are discussed using both exact and analytical solutions. Alternative routes to reach the target states are found
Strong-coupling expansion for the two-species Bose-Hubbard model
No full textTo analyze the ground-state phase diagram of Bose-Bose mixtures loaded into d-dimensional hypercubic optical lattices, we perform a strong-coupling power-series expansion in the kinetic energy term (plus a scaling analysis) for the two-species Bose-Hubbard model with onsite boson-boson interactions. We consider both repulsive and attractive interspecies interaction, and obtain an analytical expression for the phase boundary between the incompressible Mott insulator and the compressible superfluid phase up to third order in the hoppings. In particular, we find a re-entrant quantum phase transition from paired superfluid (superfluidity of composite bosons, i.e., Bose-Bose pairs) to Mott insulator and again to a paired superfluid in all one, two, and three dimensions, when the interspecies interaction is sufficiently large and attractive. We hope that some of our results could be tested with ultracold atomic systems
Vibrational quenching at ultralow energies: calculations of the Li-2((1)Sigma(+)(g);nu >> 0)+He superelastic scattering cross sections
No full textAccurate quantum calculations have been carried out at ultralow energies (from 10(-2) to 10(-6) cm(-1)) for the vibrational deexcitation of Li-2((1)Sigma(+)(g)) by collisions with He, starting from a broad range of initial highly excited vibrational levels. The results indicate the clear dominance of a few transitions with the smallest Delta nu changes and show the overall deexcitation cross sections to markedly depend on the initial vibrational state of the molecule, in line with earlier results on H-2+He [Balakrishan Phys. Rev. Lett. 80, 3224 (1998)] vibrational quenching. A connection is made with very recent measurements on the vibrational quenching of ultracold Cs-2 molecules in optical traps that were instead found to behave in a very different manner. Numerical experiments on the present system as well as on the H-3 reaction strongly suggest a possible explanation for such differences
Tensor renormalization group: local magnetizations, correlation functions, and phase diagrams of systems with quenched randomness
No full textThe tensor renormalization-group method, developed by Levin and Nave, brings systematic improvability to the position-space renormalization-group method and yields essentially exact results for phase diagrams and entire thermodynamic functions. The method, previously used on systems with no quenched randomness, is extended in this study to systems with quenched randomness. Local magnetizations and correlation functions as a function of spin separation are calculated as tensor products subject to renormalization-group transformation. Phase diagrams are extracted from the long-distance behavior of the correlation functions. The approach is illustrated with the quenched bond-diluted Ising model on the triangular lattice. An accurate phase diagram is obtained in temperature and bond-dilution probability for the entire temperature range down to the percolation threshold at zero temperature