Calibration transfer or standardisation aims at creating a uniform spectral response on different spectroscopic instruments or under varying conditions, without requiring a full recalibration for each situation. In the current study, this strategy is applied to construct at-line multivariate calibration models and consequently employ them in-line in a continuous industrial production line, using the same spectrometer. Firstly, quantitative multivariate models are constructed at-line at laboratory scale for predicting the concentration of two main ingredients in hard surface cleaners.
View Article and Find Full Text PDFCalibration transfer of partial least squares (PLS) quantification models is established between two Raman spectrometers located at two liquid detergent production plants. As full recalibration of existing calibration models is time-consuming, labour-intensive and costly, it is investigated whether the use of mathematical correction methods requiring only a handful of standardization samples can overcome the dissimilarities in spectral response observed between both measurement systems. Univariate and multivariate standardization approaches are investigated, ranging from simple slope/bias correction (SBC), local centring (LC) and single wavelength standardization (SWS) to more complex direct standardization (DS) and piecewise direct standardization (PDS).
View Article and Find Full Text PDFThe industrial production of liquid detergent compositions entails delicate balance of ingredients and process steps. In order to assure high quality and productivity in the manufacturing line, process analytical technology tools such as Raman spectroscopy are to be implemented. Marked chemical specificity, negligible water interference and high robustness are ascribed to this process analytical technique.
View Article and Find Full Text PDFImplementation of process analytical technology (PAT) tools in the manufacturing process of liquid detergent compositions should allow fast and non-destructive evaluation of the product quality. The aim of this study was to develop and validate a rapid method for quantifying the chemical compounds of five washing liquid precursors. Raman spectroscopy was applied in combination with a two-step multivariate modeling procedure.
View Article and Find Full Text PDFPublic health campaigns encourage people to protect themselves against skin cancer by using sunscreens and taking other protective measures. The objective is to estimate the impact of these campaigns on the rise of awareness among the general public. This study explores the prevalence and predictors of solar protection behaviour in a sample of beachgoers and compares these results to another similar study carried out 9 years earlier (i.
View Article and Find Full Text PDFJ Eur Acad Dermatol Venereol
January 2002
Acta Paediatr Scand
September 1989
A boy aged 2 years, born prematurely to Gipsy parents, presented with hypopigmentation severe encephalopathy with athetoid movements, bilateral ocular anomalies including cloudy corneas, iris atrophy and cataracts, as well as dental defects. Ultrastructural examination of the skin disclosed scare melanosomes. Although the neurologic and ocular anomalies might have been accounted for by his extreme prematurity, their association with hypomelanogenesis and dental defects support, in this patient the diagnosis of the oculocerebral hypopigmentation syndrome (Cross syndrome).
View Article and Find Full Text PDFA study of cosmetic intolerance has been undertaken in 5202 patients tested for possible contact dermatitis. Each patient has been evaluated by medical history and patch testing. Intolerance to cosmetics involved only 5.
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