Dynamic Properties of Supercooled Chlorinated Biphenyls.

A study of the dynamics of a series of biphenyl compounds having varying chlorine levels was carried out. Increasing the chlorine content increases the glass transition temperature and makes the dynamics substantially more sensitive to density changes. Nonetheless, in the vicinity of their respective glass transitions, the different liquids display very similar extents of dynamic correlation and dynamic heterogeneity. The slight narrowing of the relaxation peak with increasing chlorine follows the general trend of the effect of increasing molecular polarity. This relationship between the peak breadth and dipole moment was reproduced in molecular dynamics simulations of a simplified model of the Aroclor molecule.

Pressure densified 1,3,5-tri(1-naphthyl)benzene glass. I. Volume recovery and physical aging.

The effects of pressure densification on 1,3,5-tri(1-naphthyl)benzene (TNB) are assessed from volumetric and calorimetric measurements. The pressure densified glass (PDG) has higher density than conventional glass (CG), but unlike ultrastable TNB glass prepared using vapor deposition which also has elevated density, TNB PDG exhibits higher enthalpy and lower thermal stability than when formed at ambient pressure. PDG also exhibits anomalous physical aging. Rather than evolving monotonically toward the equilibrium density, there is an overshoot to a lower density state. Only when the density of the PDG becomes equivalent to the corresponding CG does the density begin a slow approach toward equilibrium.

Mechanism of Conductivity Relaxation in Liquid and Polymeric Electrolytes: Direct Link between Conductivity and Diffusivity.

Combining broadband impedance spectroscopy, differential scanning calorimetry, and nuclear magnetic resonance we analyzed charge and mass transport in two polymerized ionic liquids and one of their monomeric precursors. In order to establish a general procedure for extracting single-particle diffusivity from their conductivity spectra, we critically assessed several approaches previously employed to describe the onset of diffusive charge dynamics and of the electrode polarization in ion conducting materials. Based on the analysis of the permittivity spectra, we demonstrate that the conductivity relaxation process provides information on ion diffusion and the magnitude of cross-correlation effects between ionic motions. A new approach is introduced which is able to estimate ionic diffusivities from the characteristic times of conductivity relaxation and ion concentration without any adjustable parameters. This opens the venue for a deeper understanding of charge transport in concentrated and diluted electrolyte solutions.

Haematological malignancies presenting with acute liver injury: a single-centre experience.

INTRODUCTION: Early recognition and identification of the underlying cause of acute liver injury (ALI) is crucial in instituting medical treatment and assessing the need for liver transplantation. Haematological malignancies have been reported to present as ALI with progression to acute liver failure but experience is limited. AIM: Review our experience of ALI secondary to haematological malignancies. PATIENTS AND METHODS: Patients admitted to the liver unit with ALI secondary to a haematological malignancy between 1996 and 2006 were identified. A retrospective review was made of their case notes and our database. RESULTS: Of the 752 cases of ALI, six cases of ALI secondary to haematological malignancy were identified. Common features were a prodromal illness (median duration of 5 weeks; range 2-6 weeks) and jaundice (median bilirubin 208 micromol/l; range 112-238 micromol/l). The majority of patients (5/6) had hepatomegaly. Liver biopsy was performed in two patients and confirmed the diagnosis in both cases. In other cases, the diagnosis was made following lymph node biopsy (1), bone marrow examination (2) or from post-mortem examination (1). Median time from jaundice to encephalopathy was 12 days; range 1-22 days. A single patient underwent liver transplantation but died in the immediate post-operative period. All patients died soon after admission with a median survival of 8 days (range 3-26 days). CONCLUSION: Haematological malignancy should be considered in ALI patients presenting with a prodromal illness, jaundice and hepatomegaly. Biopsy is essential to confirm the diagnosis but the benefit of definitive therapy such as chemotherapy and/or transplantation in this setting is unclear and survival is poor.

Carbamazepine-induced acute liver failure as part of the DRESS syndrome.

Carbamazepine is a widely used drug. It is commonly associated with hepatic abnormalities, ranging from an asymptomatic rise in liver function tests to acute liver failure. The most severe reaction occurs as part of a generalised hypersensitivity reaction, also known as drug reaction, eosinophilia and systemic symptoms (DRESS). We describe a case of a young adult who presented with non-specific symptoms, which progressed to fulminant hepatic failure, displaying the hallmarks of DRESS. We highlight the need for awareness of such an association.