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The fourteen sample were collected from three outcrops from the Ujeon Coast of the southwestern Korean Peninsula. A single-aliquot regenerative-dose(SAR) optically stimulated luminescence(OSL) and single-grain post-infrared infrared stimulated luminescence(pIR-IRSL) were applied to quartz grains of 4- 11μm in diameter and K-feldspar grains of 180-212 μm in diameter, respectively. As a result of finegrained quartz OSL, the OSL ages range from 127±8.12 ka to 0.15±0.01 ka and are mostly in stratigraphic order. In contrast, the age reversal occurred in the lower part. In the case of the fine-grained quartz, equivalent dose (De) steadily increased throughout the sequence. And, most aliquots passed the acceptance criteria to check the SAR suitability. Also, the shape of the decay curve is dominated by the fast component. A pIR- IRSL using K-feldspar was applied to the same sample to determine whether the age underestimation was caused by saturation of equivalent dose in quartz and for extending the age range. Despite the ~20% increase in pIR-IRSL ages of K-feldspar single grain compared with finegrained quartz ages, the age re- versal still existed in the same section as fine-grained quartz OSL. The age reversal may have arisen mainly from a sudden increase of 150% dose rate to the lower part. On significant potential error in dose rate determination is the non-consideration of the attenuation of organic-rich sediments and intercalation of low dose layer. The dose attenuation caused by organic material is substantial and our correction may not be sufficient for this. In this study, an experiment was conducted on the dose rate measurement and the effect of the direct organic layer to overcome the limitations of dose rate measurement. Also, the reliability of OSL ages from the high-dose linear region of the dose-response curve was considered. [ABSTRACT FROM AUTHOR]

BACKGROUND: A clinical classification system has been developed to define the severity and predict the prognosis of subjects with non-cystic fibrosis (CF) bronchiectasis. We aimed to identify laboratory parameters that are correlated with the bronchiectasis severity index (BSI) and FACED score. METHODS: The medical records of 107 subjects with non-CF bronchiectasis for whom BSI and FACED scores could be calculated were retrospectively reviewed. The correlations between the laboratory parameters and BSI or FACED score were assessed, and multiple-linear regression analysis was performed to identify variables independently associated with BSI and FACED score. An additional subgroup analysis was performed according to sex. RESULTS: Among all of the enrolled subjects, 49 (45.8%) were male and 58 (54.2%) were female. The mean BSI and FACED scores were 9.43 ± 3.81 and 1.92 ± 1.59, respectively. The serum albumin level (r = -0.49), bilirubin level (r = -0.31), C-reactive protein level (r = 0.22), hemoglobin level (r = -0.2), and platelet/lymphocyte ratio (r = 0.31) were significantly correlated with BSI. Meanwhile, serum albumin (r = -0.37) and bilirubin level (r = -0.25) showed a significant correlation with the FACED score. Multiple-linear regression analysis showed that the serum bilirubin level was independently associated with BSI, and the serum albumin level was independently associated with both scoring systems. Subgroup analysis revealed that the level of uric acid was also a significant variable independently associated with the BSI in male bronchiectasis subjects. CONCLUSIONS: Several laboratory variables were identified as possible prognostic factors for non-CF bronchiectasis. Among them, the serum albumin level exhibited the strongest correlation and was identified as an independent variable associated with the BSI and FACED scores. [ABSTRACT FROM AUTHOR]