Hard sphere colloidal dispersions: Mechanical relaxation pertaining to thermodynamic forces

The complex viscosity of sterically stabilized (hard) silica spheres in cyclohexane has been measured between 80 Hz and 170 kHz with torsion pendulums and a nickel tube resonator. The observed relaxation behaviour can be attributed to the interplay of hydrodynamic and thermodynamic forces. The validity of the Cox-Merz rule is checked

Adhesive Hard-Sphere Colloidal Dispersions. A Small-Angle Neutron-Scattering Study of Stickiness and the Structure Factor

Small-angle neutron-scattering structure factor measurements were made on sterically stabilized silica spheres dispersed in benzene up to volume fractions of 0.30. Benzene is only a marginal solvent for the stabilizing layer on the surface of the particles. The particles are made attractive by lowering temperature. This attraction is modeled by a square well potential, the depth of which varies with temperature. At the highest temperature studied, our experimental system behaved effectively as an assembly of hard spheres, whereas at the lowest temperature the system approaches a spinodal. Using Baxter's theory we were able to evaluate the interaction parameters and to calculate the structure factor. Experimental structure factors were satisfactorily reproduced over the entire temperature range studied

Quantification of the spread of Salmonella and the effect of 2 feed additives

The aim of this experiment was to quantify the spread of Salmonella Typhimurium in weaned piglets by calculating R0 values. In addition, the effect of 2 feed additives, AROMABIOTIC“ and Shiitake mushroom, on the spread of Salmonella Typhimurium was evaluated. Fifty-nine piglets were allocated to 4 groups: AROMABIOTIC“ (A, n=16), Shiitake mushroom (B, n=16), positive (C, n=16) and negative controls (D, n=11). Half of the piglets of group A, B and C were experimentally inoculated with Salmonella Typhimurium, other piglets were used as susceptibles. Based on Salmonella isolation in faecal swabs, R0 values (95% C.I.) were 4.26 (1.40-34.69), 1.83 (0.86-9.38) and 4.29 (1.09-13.71) for group A, B and C, respectively. None of the measured parameters did indicate significant differences between the groups. Mortality rate was high in all 4 groups, what makes it necessary to repeat the experiment

Using the behavior change wheel to identify and understand key facilitators and barriers for lifestyle care for postmenopausal breast cancer survivors:A delphi-study

BackgroundOptimal approaches to promote sustained adherence to lifestyle and bodyweight recommendations in postmenopausal breast cancer (PMBC) survivors are lacking.PurposeThis Delphi-study aims to identify and understand expert-opinion on potential barriers and facilitators for promoting adherence to these lifestyle and bodyweight recommendations in (clinical) care for PMBC survivors, and to determine potential effective intervention strategies.MethodsThe expert panel consisted of oncology Health Care Professionals (HCPs) (N = 57), patient advocates (N = 5), and PMBC survivors (N = 38). They completed three questionnaires: Q1—idea generation; Q2—validation and prioritization; Q3—ranking. The Behavior Change Wheel was used as theoretical framework for analysis. Thematic analysis was applied to identify key overarching themes based on the top-ranked facilitators and barriers. Potential Behavior Change Techniques (BCTs) and intervention strategies were identified using the Behavior Change Technique Taxonomy version 1 and the Behavior Change Wheel.ResultsEleven core categories of key barriers/facilitators for the promotion of adherence to recommendations for lifestyle and bodyweight among PMBC survivors were identified. For each core category, relevant BCTs and practical potential intervention strategies were selected based on suggestions from the expert panel. These included: increasing knowledge about the link between lifestyle and cancer; enabling self-monitoring of lifestyle behaviors followed by evaluation; offering group lifestyle counseling for PMBC survivors, enhancing social support for favorable lifestyle behaviors; and stimulating multidisciplinary collaboration among HCPs.ConclusionsFindings provide valuable insight for the development of interventions changing behavior of PMBC survivors and HCPs toward increased healthy lifestyle (support) behavior

Improving the evaluation of worldwide biomedical research output: classification method and standardised bibliometric indicators by disease

Merit, Expertise and Measuremen

The interlayer cohesive energy of graphite from thermal desorption of polyaromatic hydrocarbons

We have studied the interaction of polyaromatic hydrocarbons (PAHs) with the basal plane of graphite using thermal desorption spectroscopy. Desorption kinetics of benzene, naphthalene, coronene and ovalene at sub-monolayer coverages yield activation energies of 0.50 eV, 0.85 eV, 1.40 eV and 2.1 eV, respectively. Benzene and naphthalene follow simple first order desorption kinetics while coronene and ovalene exhibit fractional order kinetics owing to the stability of 2-D adsorbate islands up to the desorption temperature. Pre-exponential frequency factors are found to be in the range $10^{14}$-$10^{21} s^{-1}$ as obtained from both Falconer--Madix (isothermal desorption) analysis and Antoine's fit to vapour pressure data. The resulting binding energy per carbon atom of the PAH is $52\pm$5 meV and can be identified with the interlayer cohesive energy of graphite. The resulting cleavage energy of graphite is $61\pm5$~meV/atom which is considerably larger than previously reported experimental values.Comment: 8 pages, 4 figures, 2 table