Air quality status in Greater Thessaloniki Area and the emission reductions needed for attaining the EU air quality legislation.

This paper aims at imprinting the urban air quality status and assessing the impact of various emission reduction scenarios on the photochemical and particulate matter air pollution levels in the Greater Thessaloniki Area, Greece. In particular, it is investigated under which conditions compliance with the EU air quality legislation can be achieved. For this purpose, the Ozone Fine Structure model is applied for a full calendar period (reference year 2002), as well as for specific scenarios, corresponding to predefined emission reductions for 2010. The model results for photochemical and particulate matter air pollution levels in 2002 agree fairly well with the observations. Predictions for 2010 indicate that significant improvement towards the EU legislation requirements can be achieved for certain emission reduction scenarios. However, an overall strategy will also have to include additional local scale measures.

Assessment of body volume using three-dimensional photonic scanning.

Measurement of body volume (BV) can be used to estimate body composition using two- or multicomponent models. The traditional approach, underwater weighing (UWW), is awkward and unsuitable for many subjects. A newer alternative, whole body air displacement plethysmography (ADP), is less demanding but still unsuitable for young children, who may not remain still during the measurement. We have, therefore, considered whether a novel approach, three-dimensional photonic scanning, is a viable alternative. Duplicate measurements of body volume were obtained in 22 adults (11 of each sex; mean [SD] BMI, 21.8 [2.5] kg/m2) by UWW, ADP, and a Hamamatsu Bodyline Scanner (HBS) (Hamamatsu, Japan). Subjects wore a tight-fitting swimming costume for all three measurements, which were performed within one day of each other. Scans lasted 10 seconds, with the subject standing in a predefined position. The body surface skin was reconstructed using a B-spline-fitting model. In UWW, lung volume (LV) was measured simultaneously with underwater weight. In ADP and HBS, LV was predicted from weight and height. Results were compared using correlation and Bland and Altman analysis. Correlation analysis indicated that the scanner successfully ranked subjects in terms of BV. However, Bland and Altman analysis demonstrated that, relative to both UWW and ADP, HBS measured BV without bias but with limits of agreement between individuals of > 2 liters, equivalent to approximately 20% fat. Scan precision was 0.57 liter, or 4.1% fat. Although HBS cannot yet measure BV with sufficient accuracy to predict fatness, much of the error is probably due to difficulties in standardizing LV during the scan. Simultaneous measurement of LV with volume by HBS is expected to improve limits of agreement substantially. Occlusion is also an important source of error. The method offers many advantages over alternative techniques, because the measurement is brief, noninvasive, and suitable for repeat measurements.