Kinetics of in situ epoxidation of hemp oil under heterogeneous reaction conditions: an overview with preliminary results

Epoxidised hemp oil (EHO) was synthesised in the laboratory by reacting hemp oil (HO) with peroxyacetic acid (PA) in a batch reactor. The peroxyacetic acid was formed in situ from acetic acid (AA) and hydrogen peroxide (H2O2) in the presence on an acidic ion exchange resin (Amberlite IR-120) as catalyst. The overall reaction can be thought of as having two components. The first being epoxidation, a homogenous reaction which occurs at the interface of the aqueous phase and the HO phase while the second is the formation of PA, a heterogeneous reaction at the interface of the aqueous phase and the solid catalyst phase. The overall reaction kinetics were modelled by applying the Langmuir-Hinshelwood-Hougen-Watson (LHHW) model to heterogeneous reactions. Of the steps in the reaction it is postulated that the formation of PA is rate limiting, while the epoxidation occurs comparatively fast negating the requirement for an additional homogenous model. The diffusion steps in the reaction are also ignored in the kinetic model as it is believed that their effects are negligible due to intensive mixing in the batch reactor. Experiments were used to determine the optimal molar ratios of reactants and it was found that at these conditions 88% conversion of double bonds to epoxy groups occurred. The kinetic model was found to be in good agreement with the experimental results

The 3-dimensional Fourier grid Hamiltonian method

A method to compute the bound state eigenvalues and eigenfunctions of a Schr\"{o}dinger equation or a spinless Salpeter equation with central interaction is presented. This method is the generalization to the three-dimensional case of the Fourier grid Hamiltonian method for one-dimensional Schr\"{o}dinger equation. It requires only the evaluation of the potential at equally spaced grid points and yields the radial part of the eigenfunctions at the same grid points. It can be easily extended to the case of coupled channel equations and to the case of non-local interactions.Comment: 13 pages, 1 figure. RevTeX file. To appear in J. Comput. Phy

Effects of amino acids and glucose on mesangial cell aminopeptidase a and angiotensin receptors

Effects of amino acids and glucose on mesangial cell aminopeptidase a and angiotensin receptors.BackgroundHigh protein diets and diabetes increase renal renin angiotensin system (RAS) activity, which is associated with glomerular injury. Aminopeptidase A (APA) is a cell surface metalloprotease that degrades angiotensin II (AII) in the mesangium. Mesangial cells (MC) also possess receptors for AII; the type 1 (AT1 receptor) promotes proliferation and fibrosis, while the type 2 (AT2 receptor) opposes these effects. We evaluated whether amino acids and glucose alter expression of APA, AT1 receptor and AT2 receptor in a manner that further augments RAS activity.MethodsConfluent rat MC were grown in serum-free media for 48 hours prior to exposing to experimental conditions: control (C), high amino acids (HA, mixed amino acid solution added to raise concentrations 5- to 6-fold over C), high glucose (HG 30, mM glucose). Semi-quantitative RT-PCR was used to assess mRNA for APA, AT1 receptor, AT2 receptor, and β-actin. Values are expressed relative to βbgr; actin.ResultsBoth HA and HG reduced APA mRNA (HG 1.13 ± 0.19, HA 1.12 ± 0.16 versus C 1.27 ± 0.16 P < 0.05, N = 8). HA increased AT1 receptor mRNA (HA 2.11 ± 0.43 versus C 1.14 ± 0.28 P < 0.05, N = 8). HG increased AT2 receptor mRNA (HG 1.31 ± 0.43 versus C 0.82 ± 0.33 P < 0.05, N = 6).ConclusionsA reduction of APA, in response to high levels of amino acids or glucose, could contribute to increased AII as a result of decreased degradation in MC. The effect of amino acids to increase AT1 receptor expression may further enhance adverse hemodynamic and pro-fibrotic actions of AII. Conversely, glucose increased AT2 receptor expression, which could modulate responses mediated by the AT1 receptor

Household Pesticides and the Risk of Wilms Tumor

BACKGROUND: Previous epidemiologic studies have suggested that exposure to pesticides in utero and during early childhood may increase the risk for development of childhood cancer, including Wilms tumor, a childhood kidney tumor. OBJECTIVES: In this analysis we evaluated the role of residential pesticide exposure in relation to the risk of Wilms tumor in children using data from a North American case–control study. METHODS: The National Wilms Tumor Study Group (NWTSG) collected information on exposure to residential pesticides from the month before pregnancy through the diagnosis reference date using detailed phone interviews from 523 case mothers and 517 controls frequency matched on child’s age and geographic region and identified by list-assisted random digit dialing. Pesticides were grouped according to type of pesticide and where they were used. RESULTS: A slightly increased risk of Wilms tumor was found among children of mothers who reported insecticide use [odds ratio (OR) = 1.4, 95% confidence interval (CI), 1.0–1.8; adjusted for education, income, and the matching variables]. Results from all other categories of pesticides were generally close to the null. CONCLUSIONS: This study is the largest case–control study of Wilms tumor to date. We were unable to confirm earlier reports of an increased risk for Wilms tumor among those exposed to residential pesticides during pregnancy through early childhood

Documentation of spinal red flags during physiotherapy assessment

YesThe project was designed as a retrospective service evaluation using audit to assess the identification and documentation of red flags in initial assessment of patients with low back pain. Firstly, the documentation of 11 predetermined red flags was assessed. Secondly, the documentation of relevant additional information was assessed and finally, compliance with local policy to highlight positive red flag findings in the designated area on the paperwork was examined. The documentation for the majority of red flags was high, however, clear gaps were identified. Additionally, there was no evidence of further clinical consideration of positive red flags during the diagnostic process. Possible factors influencing red flag documentation are discussed and suggestions are provided to improve recording and response to clinical indicators of malignancy