Radicals in carbonaceous residue deposited on mordenite from methanol

It is shown that control of the degree of coking can lead to the observation of hyperfine structures in the carbonaceous residues deposited from methanol over mordenite (H-MOR) at temperatures relevant to the conversion of methanol to hydrocarbons. EPR measurements of the catalyst samples at various times on stream have been recorded, with a rich hyperfine splitting pattern observed in the early stages of the reaction. Interpretation of the EPR data with the aid of density functional theoretical calculations has afforded the first definitive assignment of the radical cations formed in high temperature coke. The results detail a shortlist of six species: 2,3/2,6/2,7-dimethylnaphthalenium, 2,3,6-trimethylnaphthalenium, 2,3,6,7-tetramethylnaphthalenium, and anthracenium radical cations whose proton hyperfine splitting profiles match the experimental spectra; 2,3,6,7-tetramethylnaphthalenium showed the best agreement. The observation of these particular isomers of polymethylnaphthalene suggest the formation of more highly branched polyaromatic species is less likely within the confines of the H-MOR 12-membered ring channel. These radicals formed when the catalyst is active may constitute key intermediates in the conversion of methanol to light olefins

VALUING WATER QUALITY MONITORING: A CONTINGENT VALUATION EXPERIMENT INVOLVING HYPOTHETICAL AND REAL PAYMENTS

This paper studies the preferences and willingness-to-pay for individuals for volunteer water quality monitoring programs. The study involves supporting water quality monitoring at two ponds in the state of Rhode Island. The paper uses both a hypothetical and a real-payment contingent valuation survey to directly measure individual preferences and willingness-to-pay (WTP) for volunteer water quality monitoring at the two ponds. The overall results of the study suggest that hypothetical WTP is not statistically greater than real WTP, and that the average survey respondent is willing to support water quality monitoring on one of the two ponds. The study also finds that the specified purpose of water quality monitoring and certain socioeconomic characteristics of a respondent significantly affect the respondent's decision to support volunteer water quality monitoring.Environmental Economics and Policy,

From Hela Cell Division to Infectious Diarrhoea

Hela 83 cells were grown in suspension both randomly and, synchronously using hydroxyurea which blocks cells at the Gl/8 interface. Cryosections were prepared, freeze-dried and analyzed by X-ray microanalysis. As cells moved into S and through M phases [Na] and [Cl] increased; both returned to normal levels upon re-entering Gl phase. The Na/K ratio was 1:1 in Gl phase. Infection of HeLa 83 cells in Gl phase with vaccinia virus resulted in no change in intracellular [Na]. Infection of neonatal mice with murine rotavirus was localized to villus tip enterocytes and gave rise to diarrhoea which was maximal at 72h post-infection (p.i.). Diarrhoea was preceded by ischemia of villi (18-42h p.i.) and villus shortening (maximal at 42h p.i.), and was also coincident with a dramatic regrowth of villi. At 48h p.i. a proliferative zone of electron lucent cells was observed in villus base regions. Cryosections of infected gut, taken before, during, and after infection, together with corresponding age-matched controls, were freeze-dried and analysed by X-ray microanalysis. At 48h p.i. electron lucent villus base cells were shown to be more hydrated, and, to contain higher levels of both Na and Cl and lower levels of P, S, K and Mg than corresponding control cells. These studies (we argue) increase confidence in the use of X-ray microanalysis in studying biological systems, provide some insight into the process of cell division, and constitute the basis of a new concept of diarrhoeal secretion

Hybrid smoothed particle hydrodynamics

We present a new algorithm for enforcing incompressibility for Smoothed Particle Hydrodynamics (SPH) by preserving uniform density across the domain. We propose a hybrid method that uses a Poisson solve on a coarse grid to enforce a divergence free velocity field, followed by a local density correction of the particles. This avoids typical grid artifacts and maintains the Lagrangian nature of SPH by directly transferring pressures onto particles. Our method can be easily integrated with existing SPH techniques such as the incompressible PCISPH method as well as weakly compressible SPH by adding an additional force term. We show that this hybrid method accelerates convergence towards uniform density and permits a significantly larger time step compared to earlier approaches while producing similar results. We demonstrate our approach in a variety of scenarios with significant pressure gradients such as splashing liquids

An updated interactive database for 1692 genetic variants in coagulation Factor IX provides detailed insights into haemophilia B

BACKGROUND: Genetic variants in coagulation factor IX (FIX) are associated with haemophilia B, a rare bleeding disease. F9 variants are widespread across the gene and were summarised in our FIX variant database introduced in 2013. OBJECTIVE: We rationalise the molecular basis for 598 new F9 variants and 1645 new clinical cases, making a total of 1692 F9 variants and 5358 related patient cases. METHODS: New F9 variants were identified from publications and on-line resources, and compiled into a MySQL database for comparison with the human FIXa protein structure. RESULTS: The new total of 1692 F9 variants correspond to 406 (88%) of the 461 FIX residues and now include 70 additional residues. These comprise 945 unique point variants, 281 deletions, 352 polymorphisms, 63 insertions, and 51 others. Most FIX variants were point variants, although their proportion (56%) has reduced compared to 2013 (73%), while the proportion of polymorphisms has increased from 5% to 21%.The 764 unique mild severity variants in the mature protein with known phenotypes include 74 (9.7%) quantitative type I variants and 116 (15.2%) predominantly qualitative type II variants. The remaining 574 variants types are unspecified. Inhibitors are associated with 152 haemophilia B cases out of 5358 patients (2.8%), an increase of 93 from the previous database. CONCLUSION: The even distribution of the F9 variants revealed few mutational hotspots, and most variants were associated with small perturbations in the FIX protein structure. The updated database will assist clinicians and researchers in assessing treatments for haemophilia B patients

Developing research-informed strategies for teaching 'race' and ethnicity in higher education.

No abstract provided

Factor structure of the Oxford Shoulder Score: secondary analyses of the UK FROST and PROFHER trial populations

AimsFrozen shoulder and proximal humeral fracture can cause pain, stiffness and loss of function. The impact of these symptoms on patients can be measured using the comprehensively validated, 12-item Oxford Shoulder Score (OSS). Evidence suggests that pain and function may have a differential impact on patients’ experience of shoulder conditions, and this may be important for clinical management. We therefore explored the factor structure of the OSS within the UK FROST and PROFHER trial populations.MethodsWe performed exploratory factor analysis (EFA), followed by confirmatory factor analysis (CFA), on baseline UK FROST data from 490 of the 503 trial participants. Data at 6 months post-randomisation were used for 228 of the 250 participants for the PROFHER trial.ResultsUK FROST factor extraction results, using Velicer's Minimum Average Partial and Horn's Parallel Analysis tests, suggested a unifactorial solution, but two factors were weakly indicated by the less reliable ‘Kaiser’s eigenvalue > 1’ and scree tests. We explored this further using EFA. Eight items (2 to 7, 9 and 10) loaded onto a ‘Function’ factor, three on a ‘Pain’ factor (1, 8 and 12) and item 11 cross-loaded. However, one- and two-factor models were rejected in CFA. Factor extraction of PROFHER data at 6 months demonstrated a single first-order factor solution, which was also subsequently rejected in CFA.ConclusionInsufficient evidence was found, within the constraints of the data available, to support the use of ‘Pain’ and ‘Function’ sub-scales of the OSS in either patient population

Efficacy of Atomoxetine in Adult Attention-Deficit/Hyperactivity Disorder: A Drug-placebo Response Curve Analysis

Background: The objective of this study was to evaluate the efficacy of atomoxetine, a new and highly selective inhibitor of the norepinephrine transporter, in reducing symptoms of attention-deficit/hyperactivity disorder (ADHD) among adults by using drug-placebo response curve methods. Methods: We analyzed data from two double-blind, placebo-controlled, parallel design studies of adult patients (Study I, N = 280; Study II, N = 256) with DSM-IV-defined ADHD who were recruited by referral and advertising. Subjects were randomized to 10 weeks of treatment with atomoxetine or placebo, and were assessed with the Conners Adult ADHD Rating Scales and the Clinical Global Impression of ADHD Severity scale before and after treatment. Results: Those treated with atomoxetine were more likely to show a reduction in ADHD symptoms than those receiving placebo. Across all measures, the likelihood that an atomoxetine-treated subject improved to a greater extent than a placebo-treated subject was approximately 0.60. Furthermore, atomoxetine prevented worsening of most symptom classes. Conclusion: From these findings, we conclude that atomoxetine is an effective treatment for ADHD among adults when evaluated using several criteria

Concentration Dependence of Elastic and Viscoelastic Properties of Aqueous Solutions of Ficoll and Bovine Serum Albumin by Brillouin Light Scattering Spectroscopy

The cellular environment is crowded with macromolecules of different shapes and sizes. The effect of this macromolecular crowding has been studied in a variety of synthetic crowding environments: two popular examples are the compact colloid-like Ficoll macromolecule, and the globular protein bovine serum albumin (BSA). Recent studies have indicated a significant component of bound or surface-associated water in these crowders reduces the available free volume. In this work, Brillouin light scattering experiments were performed on aqueous solutions of Ficoll 70 and Ficoll 400 with concentrations ranging from 1 wt% to 35 wt% and BSA with concentrations of 1 wt% to 27 wt%. From the dependence of spectral peak parameters on polymer concentration, we determined fundamental solution properties: hypersound velocity, adiabatic bulk modulus and compressibility, apparent viscosity, and hypersound attenuation. Existing theory that ignores intermolecular interactions can only capture the observed linear trends in the frequency shift up to a threshold concentration, beyond which a quadratic term accounting for intermolecular interactions is necessary. This likely indicates a transition from the dilute to semi-dilute regime. In the Ficoll solutions (but not BSA) we see evidence for a central mode, with a characteristic relaxation time of 20 ps, that we attribute to exchange of the bound water.Comment: 10 pages, 4 figures, 4 table

Efficacy of atomoxetine in adult attention-Deficit/Hyperactivity Disorder: a drug-placebo response curve analysis

BACKGROUND: The objective of this study was to evaluate the efficacy of atomoxetine, a new and highly selective inhibitor of the norepinephrine transporter, in reducing symptoms of attention-deficit/hyperactivity disorder (ADHD) among adults by using drug-placebo response curve methods. METHODS: We analyzed data from two double-blind, placebo-controlled, parallel design studies of adult patients (Study I, N = 280; Study II, N = 256) with DSM-IV-defined ADHD who were recruited by referral and advertising. Subjects were randomized to 10 weeks of treatment with atomoxetine or placebo, and were assessed with the Conners Adult ADHD Rating Scales and the Clinical Global Impression of ADHD Severity scale before and after treatment. RESULTS: Those treated with atomoxetine were more likely to show a reduction in ADHD symptoms than those receiving placebo. Across all measures, the likelihood that an atomoxetine-treated subject improved to a greater extent than a placebo-treated subject was approximately 0.60. Furthermore, atomoxetine prevented worsening of most symptom classes. CONCLUSION: From these findings, we conclude that atomoxetine is an effective treatment for ADHD among adults when evaluated using several criteria