Notes: We present a new method for measuring time-resolved photoluminescence on a time scale of microseconds and milliseconds using correlational analysis, and we demonstrate it to work on porous silicon and GaP:Fe. We modulate the pumping laser with a pseudorandom binary sequence which yields correlational properties similar to white noise. The photoluminescence decay is computed via cross correlation of the detector signal with the pumping sequence. The presented method is highly sensitive, simple in application, and inexpensive.

Notes: We study the recombination mechanism of the visible photoluminescence (PL) S-band in p-doped porous Si layers by time-resolved photoluminescence. From the observed "stretched-exponential'' PL decays we present a simple yet accurate evaluation method for lifetime distributions G(τ) and average recombination lifetimes 〈τ〉. The average lifetimes feature a strong temperature dependence and a characteristic thermal activation energy of 10–20 meV for low temperatures. Our results are discussed within the models of quantum-confined exciton recombination and surface state recombination.

Notes: Results of modulated photocurrent measurements in the temperature range between 180 and 300 K on polycrystalline CuIn(S,Se)2 thin films are presented. Modeling of the obtained phase shifts implies a continuous energetic distribution of traps in the band gap. A superposition of an exponential energetic distribution of traps with a characteristic energy of 60 meV and a Gaussian peak with a depth of 250 meV can explain the obtained phase shift and amplitudes between 250 and 300 K. For lower temperatures a change of the transport path, reducing the effective depth of the peak in the density of states and reducing the "attempt to escape frequency'' is likely. At low temperatures the phase shift depends on the photon flux due to the separation of the demarcation levels whereas in the case of the higher temperatures no significant dependence on the light intensity could be detected.

Notes: Efficient solar energy conversion with CuInS2 thin films is reported. The copper-rich p-type absorber is prepared by thermal coevaporation. A copper to indium ratio between 1.0 and 1.8 can be tolerated with small (≤10%) solar-to-electrical conversion losses. Copper excess phases (CuS) are removed chemically. The cell structure glass/Mo/p-CuInS2/n-CdS/n+-ZnO/Al delivers 10.2% at simulated AM 1.5 conditions. The device properties are discussed based on its energy band diagram.

Notes: The in-plane thermal diffusivity of a polycrystalline diamond film has been measured to be 7.05 cm2/s with the converging thermal wave technique. This technique is shown to be simple, accurate, rapid to perform, and is independent of sample thickness and shape. Both high and low thermal diffusivity materials can be characterized with the technique.

Notes: Abstract Although routine patient education concerning periodontal disease is recommended as a means of improving oral health, strong associations between oral health knowledge and plaque or gingival inflammation scores have not been demonstrated. This study examined associations between four knowledge scales (likelihood of keeping teeth, signs of disease, role of diet, role of oral hygiene measures) and six periodontal status measures (plaque, gingivitis, calculus, probing depth, attachment loss, missing teeth) among 1088 regularly attending dental patients. In bivariate correlation analyses, there was a weak, direct association between stronger expectations of keeping teeth and better levels of periodontal health, while an inverse association between knowledge of signs of periodontal disease and better periodontal health was noted. Level of knowledge of the role of oral hygiene or of diet in periodontal disease was not associated with level of disease. When effects associated with age, sex, race, and different dental practices were held constant, these patient knowledge scales did not explain substantial proportions of variance in the periodontal disease measures. Among regular utilizers, the effects of receipt of dental care may be more determinative than level of patient knowledge.

Notes: Six stability statistics: (bi, s2di, 〈inlineGraphic alt="inline image" href="urn:x-wiley:01799541:PBR72:PBR_72_mu1" location="equation/PBR_72_mu1.gif" extraInfo="missing"/〉, 〈inlineGraphic alt="inline image" href="urn:x-wiley:01799541:PBR72:PBR_72_mu2" location="equation/PBR_72_mu2.gif" extraInfo="missing"/〉, 〈inlineGraphic alt="inline image" href="urn:x-wiley:01799541:PBR72:PBR_72_mu3" location="equation/PBR_72_mu3.gif" extraInfo="missing"/〉 and 〈inlineGraphic alt="inline image" href="urn:x-wiley:01799541:PBR72:PBR_72_mu4" location="equation/PBR_72_mu4.gif" extraInfo="missing"/〉) were estimated for maize, wheat and sorghum in different environments by using three statistical models. The significant linear portion of genotype × environment interaction for maize indicates different hybrids responded differently to environments, whereas the non-significant genotype × environment interaction (linear) were found for wheat and sorghum suggest that all genotypes responded similarly as the environments change. However, the highly significant pooled deviations (deviation from regression) for all three crops make yield predictions from the model less reliable. When regression coefficients (bi) were non-significant, s2di, became an important statistic in estimating stability. It appears that the regression coefficient, bi, was best used to estimate genotypic adaptability, whereas s2di, for stability. Maize and sorghum had negative correlations between the mean yield and stability statistics, s2di, 〈inlineGraphic alt="inline image" href="urn:x-wiley:01799541:PBR72:PBR_72_mu2" location="equation/PBR_72_mu2.gif" extraInfo="missing"/〉, 〈inlineGraphic alt="inline image" href="urn:x-wiley:01799541:PBR72:PBR_72_mu3" location="equation/PBR_72_mu3.gif" extraInfo="missing"/〉 and 〈inlineGraphic alt="inline image" href="urn:x-wiley:01799541:PBR72:PBR_72_mu4" location="equation/PBR_72_mu4.gif" extraInfo="missing"/〉, suggesting that high yield and stability are not mutually exclusive in the range of environments used in this study; however, such correlations did not occur in wheat. Thus, maize and sorghum hybrids with high yield potential and high stability could be identified and selected. Correlations between mean yield and bi, or 〈inlineGraphic alt="inline image" href="urn:x-wiley:01799541:PBR72:PBR_72_mu1" location="equation/PBR_72_mu1.gif" extraInfo="missing"/〉, were positive and significant for maize and sorghum but were non-significant for wheat, indicating that such relationships may be species specific. Under a given set of testing environments, the stability ranking associated with each maize hybrid is correlated to and depends on other hybrids included in the analysis.

Notes: Sensory ratings, respiratory behavior and eye blink rate were recorded in 11 nonsmokers exposed to a no-smoking (CONTROL) condition or to environmental tobacco smoke (ETS) from one of three kinds of cigarettes: a Kentucky reference (1R4F), an ultra-low tar (ULT) and one that heats tobacco (TEST).For each two-hour session in a controlled-environment room, two smokers “puffed” unlit cigarettes, for the CONTROL condition, or smoked 16 cigarettes to generate ETS (sidestream plus exhaled mainstream smoke). Concentrations of nicotine and respirable suspended particles (RSP) observed with the 1R4F and ULT cigarettes were 10- to 20-fold higher than those typically found in field sampling studies of office and restaurant smoking environments. The ULT and TEST cigarettes resulted in ETS analyte concentrations that were 77-100% and O-56%, respectively, of those observed with 1R4E Sensory ratings (odor, irritation, annoyance, acceptability) with the two tobacco-burning cigarettes were similar and were much greater than those recorded for the TEST or CONTROL conditions which were, in turn, rated similarly. Respiratory parameters (respiratory rate, tidal volume, expiratory time), which generally failed to discriminate the TEST and CONTROL conditions, were altered during exposure to ETS from the 1R4F and, to a lesser extent, the ULT cigarette. Eye blink rate was not significantly altered by ETS from any of the cigarettes.