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This article presents the results of the Asia Pacific Metrology Programme (APMP) pilot comparison on high transmittance haze (TH), specifically TH >40 %. Various methods, including ASTM D1003, ISO 14782, the double beam method, and the double compensation method were employed. The results revealed that ASTM D1003 is still influenced by failure to compensate for sphere throughput, even in high TH artefacts. In contrast, the other methods exhibit good consistency, as expected. This article also analyses the total transmittance (TT) and diffuse transmittance (DT) obtained using the double compensation method, theoretically capable of determining accurate TT, DT, and TH, discussing the possibility of inconsistency in the reflectance between the sphere wall and the white plate affecting the agreement.

Five NMIs within APMP, including CMS/ITRI, MSL, NIM, NIMT and KRISS from TCPR applied to the APMP technical committee initiative project for funding to carry out a pilot comparison of transmittance haze in 2012. The project started in 2014 and the final report was completed at the end of 2016. In this pilot comparison, three different haze standards were adopted, and transmittance haze for each standard was measured according to ASTM D1003 or ISO 14782. This paper presents the first results of an APMP pilot study of transmittance haze and the analysis of the variation among different haze measurement systems which are commonly used. The study shows that the variables such as sphere multiplier, transmittance distribution, fluorescence of samples and optical path of the incident beam cause discrepancies among NMIs and highlight deficiencies in current documentary standards.

The diffusion length of carriers in semiconductors is a significant parameter determining the suitability of a material for device applications. Here we describe a simple new technique to measure diffusion length and apply it to a study of two types of disordered GaN. We find the diffusion length to be of the order of microns in nanocrystalline GaN and hundreds of microns in amorphous GaON. Experimentally the method involves the defocussing of a laser spot between two contacts. The results are supported by numerical modelling of the carrier concentrations in the experiment.

We consider the evaluation of laboratory practice through the comparison of measurements made by participating metrology laboratories when the measurement procedures are considered to have both fixed effects (the residual error due to unrecognised sources of error) and random effects (drawn from a distribution of known variance after correction for all known systematic errors). We show that, when estimating the participant fixed effects, the random effects described can be ignored. We also derive the adjustment to the variance estimates of the participant fixed effects due to these random effects.

Abstract The bronchial epithelium is a potential source of growth factors that could mediate airway fibrosis during the progression of diseases such as asthma and chronic bronchitis. We report that conditioned medium (CM) from normal human bronchial epithelial cells (NHBECs) contains mitogenic activity for human lung fibroblasts that is blocked by the epidermal growth factor receptor (EGF-R) tyrosine kinase inhibitor AG1478 and by neutralizing antibodies raised against heparin-binding epidermal growth factor-like growth factor (HB-EGF). Neutralizing antibodies against other EGF-R ligands (EGF and transforming growth factor-α ) or other antibodies against growth factors (platelet-derived growth factors, insulin-like growth factor-1) had no affect on the mitogenic activity of NHBEC-CM. HB-EGF messenger RNA (mRNA) expression in NHBEC was detected by reverse transcriptase/polymerase chain reaction and Northern blot analysis. HB-EGF protein was detected by enzyme-linked immunosorbent assay. Vanadium pentoxide (V2O5), a fibrogenic metal associated with occupational asthma, caused a several-fold increase in HB-EGF mRNA expression and protein, whereas the inert metal titanium dioxide had no effect on HB-EGF expression. V2O5-induced HB-EGF mRNA expression was inhibited by the EGF-R tyrosine kinase inhibitor AG1478, the p38 mitogen-activated protein (MAP) kinase inhibitor SB203580, and the MAP kinase kinase inhibitor PD98059. Finally, HB-EGF induced the production of fibroblast growth factor (FGF)-2 by human lung fibroblasts and anti–FGF-2 antibody partially blocked the mitogenic activity of NHBEC-CM on fibroblasts. These data suggest that HB-EGF is a fibroblast mitogen produced by NHBECs and that induction of an FGF-2 autocrine loop in fibroblasts by HB-EGF accounts for part of this mitogenic activity.

The clothes we wear tell stories about us--and are often imbued with cultural meanings specific to our ethnic heritage.This concise A-to-Z encyclopedia explores 150 different and distinct items of ethnic dress, their history, and their cultural significance within the United States.The clothing artifacts documented here have been or are now.