Intra-pancreatic release of bradykinin during the course experimental pancreatitis in rat

Kallikrein/Kininogn activation is an important pathophysiological event in acute pancreatitis, leading to microcirculatory changes within the gland. Hitherto, only indirect measurements of pancreatic bradykinin formation have been performed, monitoring the peptide in the circulation and in the peritoneal exudate. In the present study, intra-pancreatic bradykinin release was assessed using microdialysis during experimental acute pancreatitis in rat. In mild, oedematous pancreatitis, induced by caerulein hyperstimulation, the levels of bradykinin within the gland were not elevated compared with those of control rats. However, in necrotic pancreatitis, induced by retrograde injection of taurocholate into the pancreatic duct, significantly elevated levels of intraglandular bradykinin were seen. Several rats in this group died whilst in a state of circulatory shock

Electron Correlation Driven Heavy-Fermion Formation in LiV2O4

Optical reflectivity measurements were performed on a single crystal of the d-electron heavy-fermion (HF) metal LiV2O4. The results evidence the highly incoherent character of the charge dynamics for all temperatures above T^* \approx 20 K. The spectral weight of the optical conductivity is redistributed over extremely broad energy scales (~ 5 eV) as the quantum coherence of the charge carriers is recovered. This wide redistribution is, in sharp contrast to f-electron Kondo lattice HF systems, characteristic of a metallic system close to a correlation driven insulating state. Our results thus reveal that strong electronic correlation effects dominate the low-energy charge dynamics and heavy quasiparticle formation in LiV2O4. We propose the geometrical frustration, which limits the extension of charge and spin ordering, as an additional key ingredient of the low-temperature heavy-fermion formation in this system.Comment: 5 pages, 3 figure

Fluorine in the solar neighborhood - is it all produced in AGB-stars?

The origin of 'cosmic' fluorine is uncertain, but there are three proposed production sites/mechanisms: AGB stars, $\nu$ nucleosynthesis in Type II supernovae, and/or the winds of Wolf-Rayet stars. The relative importance of these production sites has not been established even for the solar neighborhood, leading to uncertainties in stellar evolution models of these stars as well as uncertainties in the chemical evolution models of stellar populations. We determine the fluorine and oxygen abundances in seven bright, nearby giants with well-determined stellar parameters. We use the 2.3 $\mu$m vibrational-rotational HF line and explore a pure rotational HF line at 12.2 $\mu$m. The latter has never been used before for an abundance analysis. To be able to do this we have calculated a line list for pure rotational HF lines. We find that the abundances derived from the two diagnostics agree. Our derived abundances are well reproduced by chemical evolution models only including fluorine production in AGB-stars and therefore we draw the conclusion that this might be the main production site of fluorine in the solar neighborhood. Furthermore, we highlight the advantages of using the 12 $\mu$m HF lines to determine the possible contribution of the $\nu$-process to the fluorine budget at low metallicities where the difference between models including and excluding this process is dramatic

Detailed Abundances for the Old Population near the Galactic Center: I. Metallicity distribution of the Nuclear Star Cluster

We report the first high spectral resolution study of 17 M giants kinematically confirmed to lie within a few parsecs of the Galactic Center, using R=24,000 spectroscopy from Keck/NIRSPEC and a new linelist for the infrared K band. We consider their luminosities and kinematics, which classify these stars as members of the older stellar population and the central cluster. We find a median metallicity of =-0.16 and a large spread from approximately -0.3 to +0.3 (quartiles). We find that the highest metallicities are [Fe/H]<+0.6, with most of the stars being at or below the Solar iron abundance. The abundances and the abundance distribution strongly resembles that of the Galactic bulge rather than disk or halo; in our small sample we find no statistical evidence for a dependence of velocity dispersion on metallicity.Comment: 18 pages, 14 figures, accepted for publication in A

Existence of a phase transition under finite magnetic field in the long-range RKKY Ising spin glass Dyx_{x}Y1−x_{1-x}Ru2_{2}Si2_{2}

A phase transition of a model compound of the long-range Ising spin glass (SG) Dy$_{x}$Y$_{1-x}$Ru$_{2}$Si$_{2}$, where spins interact via the RKKY interaction, has been investigated. The static and the dynamic scaling analyses reveal that the SG phase transition in the model magnet belongs to the mean-field universality class. Moreover, the characteristic relaxation time in finite magnetic fields exhibits a critical divergent behavior as well as in zero field, indicating a stability of the SG phase in finite fields. The presence of the SG phase transition in field in the model magnet strongly syggests that the replica symmetry is broken in the long-range Ising SG.Comment: 4 pages, 4 figures, to be published in JPSJ (2010

Constraining dark matter halo properties using lensed SNLS supernovae

This paper exploits the gravitational magnification of SNe Ia to measure properties of dark matter haloes. The magnification of individual SNe Ia can be computed using observed properties of foreground galaxies and dark matter halo models. We model the dark matter haloes of the galaxies as truncated singular isothermal spheres with velocity dispersion and truncation radius obeying luminosity dependent scaling laws. A homogeneously selected sample of 175 SNe Ia from the first 3-years of the Supernova Legacy Survey (SNLS) in the redshift range 0.2 < z < 1 is used to constrain models of the dark matter haloes associated with foreground galaxies. The best-fitting velocity dispersion scaling law agrees well with galaxy-galaxy lensing measurements. We further find that the normalisation of the velocity dispersion of passive and star forming galaxies are consistent with empirical Faber-Jackson and Tully-Fisher relations, respectively. If we make no assumption on the normalisation of these relations, we find that the data prefer gravitational lensing at the 92 per cent confidence level. Using recent models of dust extinction we deduce that the impact of this effect on our results is very small. We also investigate the brightness scatter of SNe Ia due to gravitational lensing. The gravitational lensing scatter is approximately proportional to the SN Ia redshift. We find the constant of proportionality to be B = 0.055 +0.039 -0.041 mag (B < 0.12 mag at the 95 per cent confidence level). If this model is correct, the contribution from lensing to the intrinsic brightness scatter of SNe Ia is small for the SNLS sample.Comment: 11 pages, 7 figures, accepted for publication in MNRA

Extracorporeal circulation causes release of neutrophil gelatinase-associated lipocalin (NGAL).

Extracorporeal circulation (ECC) used during cardiac surgery causes activation of several inflammatory systems. These events are not fully understood but are responsible for complications during the immediate postoperative period. Neutrophil gelatinase-associated lipocalin (NGAL), a member of the expanding lipocalin family, has recently been described as an inflammatory protein. In this study, the release of NGAL into the circulation in 41 patients undergoing heart surgery with ECC was evaluated. A 4- to 5-fold elevation of the concentration of NGAL in plasma was observed during the immediate postoperative course with a rapid elimination during the first postoperative day. Four patients undergoing lung surgery (without ECC) were also studied. The plasma concentration of NGAL only increased with a factor of 1.1-2.2 over the operation. We conclude that NGAL is released into the circulation during heart surgery, probably as a result of the inflammatory activation of leukocytes initiated by the extracorporeal circulation

Toward Quantum Superposition of Living Organisms

The most striking feature of quantum mechanics is the existence of superposition states, where an object appears to be in different situations at the same time. The existence of such states has been tested with small objects, like atoms, ions, electrons and photons, and even with molecules. More recently, it has been possible to create superpositions of collections of photons, atoms, or Cooper pairs. Current progress in optomechanical systems may soon allow us to create superpositions of even larger objects, like micro-sized mirrors or cantilevers, and thus to test quantum mechanical phenomena at larger scales. Here we propose a method to cool down and create quantum superpositions of the motion of sub-wavelength, arbitrarily shaped dielectric objects trapped inside a high--finesse cavity at a very low pressure. Our method is ideally suited for the smallest living organisms, such as viruses, which survive under low vacuum pressures, and optically behave as dielectric objects. This opens up the possibility of testing the quantum nature of living organisms by creating quantum superposition states in very much the same spirit as the original Schr\"odinger's cat "gedanken" paradigm. We anticipate our essay to be a starting point to experimentally address fundamental questions, such as the role of life and consciousness in quantum mechanics.Comment: 9 pages, 4 figures, published versio