Finite Temperature Dynamical Correlations in Massive Integrable Quantum Field Theories

We consider the finite-temperature frequency and momentum dependent two-point functions of local operators in integrable quantum field theories. We focus on the case where the zero temperature correlation function is dominated by a delta-function line arising from the coherent propagation of single particle modes. Our specific examples are the two-point function of spin fields in the disordered phase of the quantum Ising and the O(3) nonlinear sigma models. We employ a Lehmann representation in terms of the known exact zero-temperature form factors to carry out a low-temperature expansion of two-point functions. We present two different but equivalent methods of regularizing the divergences present in the Lehmann expansion: one directly regulates the integral expressions of the squares of matrix elements in the infinite volume whereas the other operates through subtracting divergences in a large, finite volume. Our central results are that the temperature broadening of the line shape exhibits a pronounced asymmetry and a shift of the maximum upwards in energy ("temperature dependent gap"). The field theory results presented here describe the scaling limits of the dynamical structure factor in the quantum Ising and integer spin Heisenberg chains. We discuss the relevance of our results for the analysis of inelastic neutron scattering experiments on gapped spin chain systems such as CsNiCl3 and YBaNiO5.Comment: 54 pages, 10 figure

Quantum Quench in the Transverse Field Ising chain I: Time evolution of order parameter correlators

We consider the time evolution of order parameter correlation functions after a sudden quantum quench of the magnetic field in the transverse field Ising chain. Using two novel methods based on determinants and form factor sums respectively, we derive analytic expressions for the asymptotic behaviour of one and two point correlators. We discuss quenches within the ordered and disordered phases as well as quenches between the phases and to the quantum critical point. We give detailed account of both methods.Comment: 65 pages, 21 figures, some typos correcte

Micro-CT Based Experimental Liver Imaging Using a Nanoparticulate Contrast Agent: A Longitudinal Study in Mice

BACKGROUND: Micro-CT imaging of liver disease in mice relies on high soft tissue contrast to detect small lesions like liver metastases. Purpose of this study was to characterize the localization and time course of contrast enhancement of a nanoparticular alkaline earth metal-based contrast agent (VISCOVER ExiTron nano) developed for small animal liver CT imaging. METHODOLOGY: ExiTron nano 6000 and ExiTron nano 12000, formulated for liver/spleen imaging and angiography, respectively, were intravenously injected in C57BL/6J-mice. The distribution and time course of contrast enhancement were analysed by repeated micro-CT up to 6 months. Finally, mice developing liver metastases after intrasplenic injection of colon carcinoma cells underwent longitudinal micro-CT imaging after a single injection of ExiTron nano. PRINCIPAL FINDINGS: After a single injection of ExiTron nano the contrast of liver and spleen peaked after 4-8 hours, lasted up to several months and was tolerated well by all mice. In addition, strong contrast enhancement of abdominal and mediastinal lymph nodes and the adrenal glands was observed. Within the first two hours after injection, particularly ExiTron nano 12000 provided pronounced contrast for imaging of vascular structures. ExiTron nano facilitated detection of liver metastases and provided sufficient contrast for longitudinal observation of tumor development over weeks. CONCLUSIONS: The nanoparticulate contrast agents ExiTron nano 6000 and 12000 provide strong contrast of the liver, spleen, lymph nodes and adrenal glands up to weeks, hereby allowing longitudinal monitoring of pathological processes of these organs in small animals, with ExiTron nano 12000 being particularly optimized for angiography due to its very high initial vessel contrast

Validating a continental European charcoal calibration dataset

Large-scale training sets enabling quantitative reconstructions of past fire parameters are needed to better assess potential effects of increased fire hazard under global warming conditions. The aim of this article is to validate recently developed continental regression equations for the reconstruction of fire number, intensity and size. These transfer functions were built by linking satellite data and charcoal collected in annually sampled sediment traps. We apply these European regression equations to four annually layered lakes located on a North-South gradient in Europe. Down-core annual microscopic charcoal (MIC) and macroscopic charcoal (MAC) influx values were compared with satellite-derived time series of fire number, fire intensity and area burned. Results show that the match between predicted and observed values improves when the overall mean and median of sampled years (12 and 9 years) are considered. Especially, the comparisons of median values show a very good agreement between charcoal-inferred and satellite-observed fire-regime parameters. MIC-based predictions underestimate the variability of the observed fire parameters and MAC-based predictions overestimate it. Our results imply that median values of the fire parameters can be reconstructed well by using MIC and MAC, while it is more difficult to infer the variability of fire-regime parameters. However, when MIC- and MAC-based predictions are pooled together, the fit between observed and predicted values increases for both medians and variability. This finding suggests that MIC and MAC are complementary proxies, thus best sedimentary fire reconstructions may be achieved when they are used together. We conclude that sediment traps can be used for the construction of continental-scale training sets and that their results can be applied to Holocene sedimentary charcoal sequences

SI_Adolf_et_al_The_Holocene – Supplemental material for Validating a continental European charcoal calibration dataset

<p>Supplemental material, SI_Adolf_et_al_The_Holocene for Validating a continental European charcoal calibration dataset by Carole Adolf, Fabienne Doyon, Fabian Klimmek and Willy Tinner in The Holocene</p

Study of hydrated phases present in calcined paper sludge (metakaolinite)/saturated CaO dissolution system cured at 40 °C and 28 days of reaction

[EN] The present research is a part of an experimental study about obtaining recycled metakaolinite from a Spanish paper sludge waste as complementary cementing material. The mineral phases formation from paper sludge calcined at different temperatures (700, 750 and 800 °C) and two times of stay in the furnace (2 and 5 h) mixed with saturated lime dissolution are obtained mineral phases: C-S-H gel, stratlingite, tobermorite, hydrotalcite. The C-S-H gels generated in the first stages lose crystallinity and filled the existing holes between stratlingite and hydrotalcite. The different mineral evolves according to their stability fields toward crystalline aggregates more compact where the gels fill hollow.Peer reviewe

Donor dopamine treatment in brain dead rats is associated with an improvement in renal function early after transplantation and a reduction in renal inflammation

Brain death (BD) is associated with tissue inflammation. As dopamine treatment of BD donor rats reduces renal monocyte infiltration, we tested if this treatment affects renal function and inflammation in recipients. BD was induced in F344 rats and was maintained for 6 h in all experiments. Dopamine was given for 6 (DA6) or 3 h (DA3) from the onset of BD. Ventilated non-BD (NBD) and BD animals served as controls. Kidneys were transplanted into bilaterally nephrectomized Lewis recipients. Serum creatinine (s-crea) was measured and leukocyte infiltration was assessed 10 days after transplantation. One day after transplantation, s-crea was significantly reduced in recipients who received a renal allograft from dopamine treated BD or from NBD rats compared to BD vehicle (P <0.05). Ten days after transplantation, the number of infiltrating monocytes was significantly lower in grafts obtained from dopamine treated and from NBD rats (P <0.05). A reduced infiltration in these grafts was confirmed by Banff 97 classification. Cytokine-induced neutrophil-chemoattractant 1 and interleukin (IL)-6 mRNA expression were reduced in DA rats compared to BD controls. No difference for macrophage chemoattractant protein 1 and IL-10 were found. These findings may explain the salutary effect of donor dopamine treatment in renal transplantation

Time course of contrast enhancement within the vascular system and the liver of C57BL/6J mice (n = 3 per group) after a single i.v. injection of 100 µl ExiTron nano 6000 or ExiTron nano 12000.

<p>Measurements were performed by placing a ROI within the left ventricle (vessel contrast) and within the liver avoiding large intrahepatic vessels. The baseline level ( = 100%) refers to measurement of the relative density of the liver and the vascular system prior to administration of contrast agent.</p

A shows a volume rendering of a mouse 30 minutes after i.v. injection of ExiTron nano 12000.

<p>B is a curved maximum intensity projection in coronal orientation of the same scan. A and B demonstrate the feasibility to perform CT angiography during the early intravascular phase of the tested contrast agent. Additionally, A and B show the early contrast agent uptake by the RES with increasing contrast of liver and spleen. C is a coronally oriented curved maximum intensity projection of a mouse that did not receive contrast agent.</p

A and B show a partial diaphragmatic herniation of the left upper liver lobe in coronally (A) and sagittally (B) reconstructed maximum intensity projections of a C57BL/6J mouse 22 hours after i.v. injection of 100 µl ExiTron nano 12000.

<p>The herniated liver tissue can be easily delimited from the adjacent heart due to the positive liver contrast. C and D are micro-CT scans of the murine liver before (C) and 24 hours after (D) intravenous administration of 100 µl ExiTron nano 6000.</p