Plaque quantitiation through protein measurement

PKThis study was undertaken to establish whether the quantitation of dental plaque protein by a dye-binding method (Coomassie G-250) may be used as an index of the amount of dental plaque sampled. Ten sites were sampled in 34 children on 5 occasions at 4 month intervals. The mean protein concentration in 1391 plaque samples was 6.9 +/- 4.1 micrograms (micrograms) (mean +/- standard deviation). A three-way analysis of variance showed that the plaque protein concentration was similar at the different sampling sites in the same child (p = 0.14), but statistically significant differences were observed with respect to time of sampling (F = 36.24; p = 0.0001) and individual sampled (F = 5.69; p = 0.0001). These observations indicate that plaque bacterial counts may be expressed as units of protein concentration and this method may be useful to relate the number of viable bacteria to an estimate of the amount of plaque collected. This ratio allows standardisation for any variation in the amount of plaque collected

The SmartCulTour Toolkit.

Deliverable 7.3 of the Horizon 2020 project SmartCulTour (GA number 870708), published on theproject web site on (30-11-2022): http://www.smartcultour.eu/deliverables

The SmartCulTour Toolkit.

Deliverable 7.3 of the Horizon 2020 project SmartCulTour (GA number 870708), published on theproject web site on (30-11-2022): http://www.smartcultour.eu/deliverables

Ballistic transport, chiral anomaly and emergence of the neutral electron - hole plasma in graphene

The process of coherent creation of particle - hole excitations by an electric field in graphene is quantitatively described using a dynamic "first quantized" approach. We calculate the evolution of current density, number of pairs and energy in ballistic regime using the tight binding model. The series in electric field strength $E$ up to third order in both DC and AC are calculated. We show how the physics far from the two Dirac points enters various physical quantities in linear response and how it is related to the chiral anomaly. The third harmonic generation and the imaginary part of conductivity are obtained. It is shown that at certain time scale $t_{nl}\propto E^{-1/2}$ the physical behaviour dramatically changes and the perturbation theory breaks down. Beyond the linear response physics is explored using an exact solution of the first quantized equations. While for small electric fields the I-V curve is linear characterized by the universal minimal resistivity $\sigma =\pi /2(e^{2}/h)$%, at $t>t_{nl}$ the conductivity grows fast. The copious pair creation (with rate $E^{3/2}$), analogous to Schwinger's electron - positron pair creation from vacuum in QED, leads to creation of the electron - hole plasma at ballistic times of order $t_{nl}$. This process is terminated by a relaxational recombination.Comment: 15 pages, 5 figures

Exploring parental and driver knowledge, use and beliefs of child restraints such as infant car seats, toddler seats and booster seats in South Africa

Abstract: The purpose of this paper is to determine parents’ and drivers’ knowledge, use and beliefs of child restraints amongst lower middle-class groups in South Africa. The study was qualitative in nature, and data was collected from parents or drivers of children aged birth - 11 with a motor vehicle in Gauteng. Through the application of the convenience sampling technique, a total of 14 parents and drivers with children at selected pre-schools and primary schools, who are in the lower middleclass groups and who reside in the cities of Johannesburg, Tshwane and Ekurhuleni, were selected. The Morse and Field Approach was used to analyse the data because the steps of this data analysis method are clear, easy to follow and comprehensible. There is a lack of knowledge and usage of child restraints among lower middle-class parents and drivers within Gauteng. The results also indicate that there are variables that are predictive of age-appropriate restraint use and knowledge, and that parents hold specific beliefs around child restraints. Lastly, the results indicated that the parents and drivers have rarely seen any advertisements on child restraints in South Africa. By exploring the topic of usage, knowledge, beliefs and the social marketing of child restraints, strategies have been identified on how to overcome the major challenge of child injuries in motor vehicle accidents in South Africa. This study promotes child restraint usage on South African roads and assists organisations in South Africa to better understand that social marketing is necessary to change the behaviour of parents with regard to child restraints usage

Time evolution for quantum systems at finite temperature

This paper investigates a new formalism to describe real time evolution of quantum systems at finite temperature. A time correlation function among subsystems will be derived which allows for a probabilistic interpretation. Our derivation is non-perturbative and fully quantized. Various numerical methods used to compute the needed path integrals in complex time were tested and their effectiveness was compared. For checking the formalism we used the harmonic oscillator where the numerical results could be compared with exact solutions. Interesting results were also obtained for a system that presents tunneling. A ring of coupled oscillators was treated in order to try to check selfconsistency in the thermodynamic limit. The short time distribution seems to propagate causally in the relativistic case. Our formalism can be extended easily to field theories where it remains to be seen if relevant models will be computable.Comment: uuencoded, 14 pp in Latex, 8 ps Fig