Effect of bending on the predissociation dynamics of N2O+

In this paper we introduce a modified version of the infinite-order sudden approximation (IOSA) for rotational and bending degrees of freedom, together     

Model for vibrational predissociation of van der Waals molecules

We advance a theoretical model for vibrational predissociation (VP) of a linear triatomic molecular complex consisting of a rare-gas atom bound to diatomic, which rests on the decay of a bound state into a manifold of coupled translational continua. We explored the dependence of the VP rate on the molecular parameters of the complex, establishing an energy gap law for VP. The effects of intercontinuum coupling on the dynamics of VP were investigated.     

Selective inhibition of the K+ efflux sensitive NLRP3 pathway by Cl− channel modulation

The NLRP3 inflammasome regulates production of the pro-inflammatory cytokines interleukin-1β (IL-1β) and IL-18, and contributes to inflammation exacerbating disease. Fenamate non-steroidal anti-inflammatory drugs (NSAIDs) were recently described as NLRP3 inflammasome inhibitors via chloride channel inhibition. Fenamate NSAIDs inhibit cyclooxygenase (COX) enzymes, limiting their potential as therapeutics for NLRP3-associated diseases due to established side effects. The aim here was to develop properties of the fenamates that inhibit NLRP3, and at the same time to reduce COX inhibition. We synthesised a library of analogues, with feedback from in silico COX docking potential, and IL-1β release inhibitory activity. Through iterative screening and rational chemical design, we established a collection of chloride channel inhibiting active lead molecules with potent activity at the canonical NLRP3 inflammasome and no activity at COX enzymes, but only in response to stimuli that activated NLRP3 by a K⁺ efflux-dependent mechanism. This study identifies a model for the isolation and removal of unwanted off-target effects, with the enhancement of desired activity, and establishes a new chemical motif for the further development of NLRP3 inflammasome inhibitors.

The NLRP3 inflammasome regulates production of the pro-inflammatory cytokines interleukin-1β (IL-1β) and IL-18, and contributes to inflammation exacerbating disease.     

“I’m not very good at solving problems”: An exploration of students’ problem solving behaviours

This paper reports one aspect of a larger study which looked at the strategies used by a selection of grade 6 students to solve six non-routine mathematical problems. The data revealed that the students exhibited many of the behaviours identified in the literature as being associated with novice and expert problem solvers. However, the categories of ‘novice’ and ‘expert’ were not fully adequate to describe the range of behaviours observed and instead three categories that were characteristic of behaviours associated with ‘naïve’, ‘routine’ and ‘sophisticated’ approaches to solving problems were identified. Furthermore, examination of individual cases revealed that each student's problem solving performance was consistent across a range of problems, indicating a particular orientation towards naïve, routine or sophisticated problem solving behaviours. This paper describes common problem solving behaviours and details three individual cases involving naïve, routine and sophisticated problem solvers.     

Dielectrophoretic trapping of single leukemic cells using the conventional and compact optical measurement systems

Here, we report a microfluidic same‐single‐cell analysis to study the inhibition of multidrug resistance due to drug efflux on single leukemic cells. Drug efflux inhibition was investigated in the microfluidic chip using two different fluorescence detection systems, namely, a compact single‐cell bioanalyzer and the conventional optical detection system constructed from an inverted microscope and a microphotometer. More importantly, a compact signal generator was used to conduct dielectrophoretic cell trapping together with the compact SCB. By using the DEP force, a single acute myeloid leukemia cell was trapped in the cell retention structure of the chip. This allowed us to detect dye accumulation in the MDR leukemic cells in the presence of cyclosporine A (CsA). CsA and rhodamine 123 were used as the P‐glycoprotein inhibitor and fluorescent dye, respectively. The result showed that the Rh123 fluorescence signal in a single‐cell increased dramatically over its same‐cell control on both fluorescence detection systems due to the inhibition by CsA.     

Determination of the solid liquid interfacial energy and thereby the critical nucleus size of paracetamol in different solvents

The effect of the type of solvent on the solid liquid interfacial energy was determined by performing induction time measurements of paracetamol in methanol, 1‐propanol, acetone and water at a constant supersaturation temperature of 30 °C and different levels of supersaturation (a/a*) ranging from 1.03 to 1.24. At equal supersaturation level and temperature the induction time increases with decreasing solubility whereas the solid liquid interfacial energy decreases with increasing solubility. The interfacial energy has a minimum value of 1.45 mJ/m² in the solvent where paracetamol has a maximum solubility (methanol) whereas it has its maximum value of 2.91 mJ/m² in the solvent with minimum solubility. The interfacial energy is a function of the solubility has been established. The critical radius for homogeneous nucleation was found to be minimum in the solvent of highest solubility. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The addition polymerization of a p=c bond: a route to new phosphine polymers

Addition polymerization, the most general method of preparation for organic polymers, has successfully been extended to P=C bonds. The polymerization of a phosphaalkene has been initiated by thermolysis or with alkyllithium reagents. The unprecedented poly(methylenephosphine)s are easily oxidized using oxygen or sulfur to give air stable macromolecules. A molecular weight (M(w)) of 35000 g/mol for the poly(methylenephosphine sulfude) was estimated by light-scattering GPC.     

Isotope effects in photofragmentation of linear triatomics

We report the results of a theoretical study of isotope effects on the predissocation lifetimes, on the absorption cross sections for direct photodissociation and on the vibrational distribution of the photofragments in the photofragmentation of HCN and DCN. The deuterium isotope effect on the photofragmentation probability at 1.45 eV above the thréshold for production of CN (B²Σ) is γ_s(DCN)/γ_s(HCN) ≈ 0.2.