Educational levels and the functional dependence of ischemic stroke survivors

We evaluated the functional dependence of stroke survivors from the Study of Stroke Mortality and Morbidity, using the Rankin Scale. Out of 355 ischemic stroke survivors (with a mean age of 67.9 years), 40% had some functional dependence at 28 days and 34.4% had some functional dependence at 6 months. Most predictors of physical dependence were identified at 28 days. These predictors were: low levels of education [illiterate vs. >= 8 years of education, multivariate odds ratio (OR) = 3.7; 95% confidence interval (95%CI): 1.60-8.54] and anatomical stroke location (total anterior circulation infarct, OR = 16.9; 95%CI: 2.93-97.49). Low levels of education and ischemic brain injury influenced functional dependence in these stroke survivors. Our findings reinforce the necessity of developing strategies for the rehabilitation of stroke patients, more especially in formulating specific strategies for care and treatment of stroke survivors with low socioeconomic status.

Teeth restored using fiber-reinforced posts: in vitro fracture tests and finite element analysis

In dentistry the restoration of decayed teeth is challenging and makes great demands on both the dentist and the materials. Hence, fiber-reinforced posts have been introduced. The effects of different variables on the ultimate load on teeth restored using fiber-reinforced posts is controversial, maybe because the results are mostly based on non-standardized in vitro tests and, therefore, give inhomogeneous results. This study combines the advantages of in vitro tests and finite element analysis (FEA) to clarify the effects of ferrule height, post length and cementation technique used for restoration. Sixty-four single rooted premolars were decoronated (ferrule height 1 or 2 mm), endodontically treated and restored using fiber posts (length 2 or 7 mm), composite fillings and metal crowns (resin bonded or cemented). After thermocycling and chewing simulation the samples were loaded until fracture, recording first damage events. Using UNIANOVA to analyze recorded fracture loads, ferrule height and cementation technique were found to be significant, i.e. increased ferrule height and resin bonding of the crown resulted in higher fracture loads. Post length had no significant effect. All conventionally cemented crowns with a 1-mm ferrule height failed during artificial ageing, in contrast to resin-bonded crowns (75% survival rate). FEA confirmed these results and provided information about stress and force distribution within the restoration. Based on the findings of in vitro tests and computations we concluded that crowns, especially those with a small ferrule height, should be resin bonded. Finally, centrally positioned fiber-reinforced posts did not contribute to load transfer as long as the bond between the tooth and composite core was intact.

Comparison of three strip-type tests and two laboratory methods for salivary buffering analysis

This study evaluated the correlation between three strip-type, colorimetric tests and two laboratory methods with respect to the analysis of salivary buffering. The strip-type tests were saliva-check buffer, Dentobuff strip and CRT(®) Buffer test. The laboratory methods included Ericsson's laboratory method and a monotone acid/base titration to create a reference scale for the salivary titratable acidity. Additionally, defined buffer solutions were prepared and tested to simulate the carbonate, phosphate and protein buffer systems of saliva. The correlation between the methods was analysed by the Spearman's rank test. Disagreement was detected between buffering capacity values obtained with three strip-type tests that was more pronounced in case of saliva samples with medium and low buffering capacities. All strip-type tests were able to assign the hydrogencarbonate, di-hydrogenphosphate and 0.1% protein buffer solutions to the correct buffer categories. However, at 0.6% total protein concentrations, none of the test systems worked accurately. Improvements are necessary for strip-type tests because of certain disagreement with the Ericsson's laboratory method and dependence on the protein content of saliva.

Monte Carlo calculation of Varian 2300C/D Linac photon beam characteristics: a comparison between MCNP4C, GEANT3 and measurements

Different codes are used for Monte Carlo (MC) calculations in radiation therapy. In this research, MCNP4C and GEANT3 codes have been compared in calculations of dosimetric characteristics of Varian Clinac 2300C/D. The parameters of influence in the differences seen in dosimetric features were discussed. This study emphasizes that both MCNP4C and GEANT3 MC can be used in radiation therapy computations and their differences in photon spectra calculations have a negligible effect on percentage depth dose computations in radiation therapy.

Educational Expansion and Persistent Inequalities of Education: Utilizing the Subjective Expected Utility Theory to Explain the Increasing Participation Rates in Upper Secondary School in the Federal Republic Of Germany

This investigation attempts to answer the question why more and more parents have chosen the Gymnasium for their children's secondary school education in post‐war West Germany. Based on the theory of subjective expected utility, the crucial mechanisms of parental educational decisions have been emphasized. From this perspective it is assumed that increasing educational motivation coupled with changes in the subjective evaluation of the cost–benefit of education were important conditions for an increasing participation in upper secondary schools. These were, however, in turn, the result of educational expansion. The empirical analyses for three time‐periods in the 1960s, 1970s, and 1980s confirm these assumptions to a large degree. Additionally, empirical evidence was found to suggest that in addition to the intentions of parents and the educational career of their children, structural moments of educational expansion and their own inertia played an important role in the pupils' transition from one educational level to the next. Finally, evidence was found that persistent class‐specific educational inequality stems from a constant balance in the relative cost–benefit advantages between social classes as well as from an increasing difference of primary origin effect between social classes in the realization of their educational choice.

Poverty, Educational Attainment and Health Among America’s Children: Current and Future Effects of Population Diversification and Associated Socioeconomic Change

A complex of interrelated factors including minority status, poverty, education, health status, and other factors determine the general welfare of children in America, particularly in heavily diverse states such as Texas. Although racial/ethnic status is clearly only a concomitant factor in that determination it is a factor for which future projections are available and for which the relationships with the other factors in the complex can be assessed. After examining the nature of the interrelationships between these factors we utilize direct standardization techniques to examine how the future diversification of the United States and Texas will affect the number of children in poverty, the educational status of the householders in households in which children in poverty live and the health status of children in 2040 assuming that the current relationships between minority status and these socioeconomic factors continue into the future. In the results of the analyses, data are compared with the total population of the United States and Texas in 2040 assumed in the first simulation scenario, to have the race/ethnicity characteristics of 2008 and in the second those projected for 2040 by the U.S. Census Bureau for the nation and by the Texas State Data Center for Texas in 2040. The results show that the diversification of the population could increase the number of children in poverty in the United States by nearly 1.8 million more than would occur with the lower levels of diversification evident in 2008. In addition, poverty would become increasingly concentrated among minority children with minority children accounting for 76.2 percent of all children in poverty by 2040 and with Hispanic children accounting for nearly half of the children in poverty by 2040. Results for educational attainment show an increasing concentration of minority children in households with householders with very low levels of education such that by 2040, 85.2 percent of the increase in the number of children in poverty would be in households with a householder with less than a high school level of education. Finally, the results related to several health status factors show that children in poverty will have a higher prevalence of nearly all health conditions. For example, the number of children with untreated dental conditions could increase to more than 4 million in the United States and to nearly 500,000 in Texas. The results clearly show that improving the welfare of children in America will require concerted efforts to change the poverty, educational, and health status characteristics associated with minority status and particularly Hispanic status. Failing to do so will lead to a future in which America’s children are increasingly impoverished, more poorly educated, and less healthy and which, as a result, is an America with a more tentative future.

Antenna Simulations and Measurements of Focal Plane Array Facet Reflectors

We present a conceptual prototype model of a focal plane array unit for the STEAMR instrument, highlighting the challenges presented by the required high relative beam proximity of the instrument and focus on how edge-diffraction effects contribute to the array's performance. The analysis was carried out as a comparative process using both PO & PTD and MoM techniques. We first highlight general differences between these computational techniques, with the discussion focusing on diffractive edge effects for near-field imaging reflectors with high truncation. We then present the results of in-depth modeling analyses of the STEAMR focal plane array followed by near-field antenna measurements of a breadboard model of the array. The results of these near-field measurements agree well with both simulation techniques although MoM shows slightly higher complex beam coupling to the measurements than PO & PTD.