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More than half of South Africans live below the poverty line. Indirect medical costs can contribute significantly to the financial burden of patients seeking medical care. The aim of this study was to determine the expenses incurred by patients and/or their escorts during a visit to the emergency centre (EC).Patients and/or their escorts presenting to an EC in Johannesburg were asked to complete the study questionnaire relating to expenses incurred during a visit to the EC.Of the total 396 participants that completed the questionnaire, 108 (27.2%) did not have any source of income, 146 (36.9%) were the sole breadwinner in their household and 36 (9.1%) belonged to zero-income households. Among those earning ≤R2000 per month, the mean expenses relating to the EC visit was R240 (SD R372), equating to an average of 33.2% of mean monthly income. Transport costs were the most common expense (n=302, 76.3%), while general practitioner (GP) fees incurred prior to the EC visit accounted for the bulk of the expenses (median R450, IQR 350-820). Participants that earnedR2000 per month were significantly more likely to incur GP fees (p =0.012), while those earning ≤R2000 per month were significantly more likely to take a loan to cover EC related expenses (p =0.014).A visit to the EC can have a substantial financial impact on patients and their accompanying escorts in South Africa. Strategies should be aimed at identifying and assisting those that are in need of financial assistance to cover indirect healthcare costs.

Continuous theta burst stimulation (cTBS) is thought to reduce cortical excitability and modulate functional connectivity, possibly by altering cortical inhibition at the site of stimulation. However, most evidence comes from the motor cortex and it remains unclear whether similar effects occur following stimulation over other brain regions. We assessed whether cTBS over left dorsolateral prefrontal cortex altered gamma aminobutyric acid (GABA) concentration, functional connectivity and brain dynamics at rest, and brain activation and memory performance during a working memory task. Seventeen healthy individuals participated in a randomised, sham-controlled, cross-over experiment. Before and after either real or sham cTBS, magnetic resonance spectroscopy was obtained at rest to measure GABA concentrations. Functional magnetic resonance imaging (fMRI) was also recorded at rest and during an n-back working memory task to measure functional connectivity, regional brain activity (low-frequency fluctuations), and task-related patterns of brain activity. We could not find evidence for changes in GABA concentration (P=0.66, Bayes factor [BF10]=0.07), resting-state functional connectivity (P(FWE)>0.05), resting-state low-frequency fluctuations (P=0.88, BF10=0.04), blood-oxygen level dependent activity during the n-back task (P(FWE) >0.05), or working memory performance (P=0.13, BF10=0.05) following real or sham cTBS. Our findings add to a growing body of literature suggesting the effects of cTBS are highly variable between individuals and question the notion that cTBS is a universal ‘inhibitory’ paradigm.

Where the Everyday Begins is a study of environment and everyday life. It uses innovative research methods to bear witness to the ways by which environment defines everyday life. And its lively narrative pulls together a multitude of observations that reveal incredible details about the social and material ecologies that bind the world.

Hydrogen storage and emission from Ni/Ce (0.1:1) composite oxides, prepared by the co-precipitation method at −2 °C, 22 °C and 60 °C using triethylamine as the precipitating agent, are investigated. The as-prepared uncalcined materials exhibit small amounts of H2 emission even without prior exposure to H2, with the amount dependent on the synthesis temperature. Examination of the CO, CO2 and H2O emission profiles suggest a link between the presence and stability of carbonate species within these composite materials and the H2 emission. Following activation in pure hydrogen at 250 °C, all samples show increased H2 emission levels but it is only in the sample synthesised at 60 °C that a simultaneous decrease in the H2 emission temperature is found. H2O emission below 250 °C in the activated material indicates that this also originates from hydrogen stored in the material. The activation conditions are shown to have a significant impact on the level of H2 interaction with these materials. A marked increase of the crystallite size with synthesis temperature, from 1.7 nm at −2 °C to 11.7 nm at 60 °C, is also found. The difference in of H2 interaction is associated with a change in the nature/morphology of the materials precipitated at the different temperatures.

The Summer Explorations and Research Collaborations for High School Girls (SEARCH) Program, held annually since 2004 at Mount Holyoke College in the US, was created for talented high school girls to explore mathematics beyond that taught in high school. Our study, which focuses on factors that facilitate or inhibit the pursuit of higher level mathematics by girls, is centered on the 2006 SEARCH Program. We present a combination of qualitative and quantitative data drawn from student journals written during SEARCH, program evaluations written at the end of SEARCH, post-program interviews, and comparisons with two peer group samples. From this data we point to important factors, such as developing a mathematical voice, gaining a broader view of advanced mathematics, being challenged in a supportive atmosphere, and having a positive stance toward risk-taking, that may help to maintain the interest of talented girls in advanced mathematical studies.

The effect of thermal oxidation on the hydrogen storage properties of carbon nano-horns was investigated by gravimetric and electrochemical methods. The pristine nano-horn sample was oxidised at 673 K in air for different periods (15, 30 and 60 min) and the resulting materials were characterised. The N(2) adsorption experiments reveal a marked increase in the surface area, from 267 m(2) g(-1), for the pristine sample, up to 1360 m(2) g(-1) for the sample oxidised for the 60 min period, and a reduction in the average pore diameter. The gravimetric investigation, conducted at low temperature (77 K) showed an increase in the hydrogen storage, from 0.75 wt% for the pristine sample up to 2.60 wt% for the oxidised material. Reproducible and stable hydrogen storage was found for all the samples examined apart from the sample oxidised for 60 min. For the latter, a decrease in the amount of hydrogen stored between the first and second cycles was found. Electrochemical loading of hydrogen in the samples was performed at room temperature (298 K) in alkaline solution by the galvanostatic charge/discharge technique. The results obtained here however show a much lower hydrogen storage level by the samples as compared to the gas storage method, with a maximum value of 0.124 wt% H(2) and with very little dependence on the thermal oxidation treatment.

The properties of dried (but not calcined) coprecipitated nickel ceria systems have been investigated in terms of their hydrogen emission characteristics following activation in hydrogen. XRD and BET data obtained on the powders show similarities to calcined ceria but it is likely that the majority of the material produced by the coprecipitation process is largely of an amorphous nature. XPS data indicate very little nickel is present on the outermost surface of the particles. Nevertheless, the thermal analytical techniques (TGA, DSC and TPD-MS) indicate that the hydrogen has access to the catalyst present and the nickel is able to generate hydrogen species capable of interacting with the support. Both unactivated and activated materials show two hydrogen emission features, viz. low temperature and high temperature emissions (LTE and HTE, respectively) over the temperature range 50 and 500 degrees C. A clear effect of hydrogen interaction with the material is that the activated sample not only emits much more hydrogen than the corresponding unactivated one but also at lower temperatures. H(2) dissociation occurs on the reduced catalyst surface and the spillover mechanism transfers this active hydrogen into the ceria, possibly via the formation and migration of OH(-) species. The amount of hydrogen obtained (~0.24 wt%) is approximately 10x higher than those observed for calcined materials and would suggest that the amorphous phase plays a critical role in this process. The affiliated emissions of CO and CO(2) with that of the HTE hydrogen (and consumption of water) strongly suggests a proportion of the hydrogen emission at this point arises from the water gas shift type reaction. It has not been possible from the present data to delineate between the various hydrogen storage mechanisms reported for ceria.

We report results from a series of PIC simulations carried out to investigate the interaction of intense laser light with overdense plasma and in particular, aspects of the harmonic emission spectrum generated in these interactions. Recent observations of emission in this range by Watts et al. (2002) show emission above the 20th harmonic extending to the 37th with conversion efficiencies of order 10^-6 with this spectrum showing distinct, if variable, modulation of between two and four harmonics. This spectral feature proved highly sensitive to the incident intensity, with more pronounced modulation at higher intensities. These authors also reported results from a set of model PIC simulations which showed a modulated emission spectrum across the entire harmonic range, but with a wider modulation bandwidth. In the results to be presented we report on features of the emission spectrum across a wide parameter range and its dependence on the detailed structure of the plasma density profile. While we do see evidence of a modulated spectrum, this appears to be sensitive not only to the incident intensity but to the plasma density profile. In addition plasma emission present further complicates the harmonic emission spectrum. Our results lead us to conclude that attempts to interpret modulation in emission spectra in terms of one particular theoretical model and from this to infer the dynamics of the critical surface may be misguided.

With the current attempts to encourage renewable energy and to promote nuclear energy as a way of weaning us off fossil fuels, we really need to make our explanations clearer and stop using the terms "power" and "energy" as if they are interchangeable.

Richard W. Budd and Brent D. Ruben, Beyond Media: New Approaches to Mass Communication (Rochelle Park, N.J.: Hayden Book Company, 1979—$9.95, paper) Robert F, Rich,"Knowledge Production and Utilization," a special issue of American Behavioral Scientist 22:3 (January/February 1979) James and Jean Morrow The Grammar of Media Kit (Rochelle Park, N.J.: Hayden Book Company, 1978—$295 for the complete set which includes 5 super-8mm films, 4 LP records, 20 comic books, 20 student workbooks, and one teacher's handbook, all available on a 30-day examination basis). Charles U. Larson Persuasion: Reception and Responsibility (Belmont, Calif.: Wadsworth Publishing, 1979– S9.95, paper) Frank Brady and Joann Lawless' Brady & Lawless's Favorite Bookstores (Mission, Kansas: Sheed Andrews and McMeel, 1978—$12.95) Alan Wells, Mass Media and Society (Palo Alto, Calif.: Mayfield Publishing Co., 1979—price not given, paper) John L. Hulteng The News Media: What Makes Them Tick? (Englewood Cliffs, N.J.: Prentice-Hall, 1979—$7.9...