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Formaldehyde, CH2O, mixing ratios are reported for the central Pacific troposphere from a series of 41 flights, which took place in March-April 1999 as part of the NASA Pacific Exploratory Mission (PEM) -Tropics B mission. Ambient CH2O was collected in aqueous media and quantified using an enzyme-derivatization fluorescence technique. Primary calibration was performed using aqueous standards and known flow rates. Occasionally, CH2O gas standard additions to ambient air were performed as a secondary calibration. Analytical blanks were determined by replacing ambient air with pure air. The estimated precision was ±30 pptv and the estimated accuracy was the sum of ±30 parts per trillion by volume (pptv) ±15% of the measured value. Approximately 25% of the observations were less than the instrumental detection limit of 50 pptv, and 85% of these occurred above 6 km. CH2O mixing ratios decreased with altitude; for example, near the equator the median value in the lowest 2 km was 275 pptv, decreased to 150 pptv by 6 km and was below 100 pptv above 8 km. Between 130 and 170 W and below 1km, a small variation of CH2O mixing ratio with latitude was noted as near-surface median mixing ratios decreased near the equator (275 pptv) and were greater on either side (375 pptv). A marked decrease in near-surface CH2O (200 pptv) was noted south of 23° S on two flights. Between 3° and 23° S, median CH2O mixing ratios were lower in the eastern tropical Pacific than in the western or central Pacific; nominal differences were >100 pptv near the surface to ∼100 pptv at midaltitude to ∼50 pptv at high altitude. Off the coast of Central America and Mexico, mixing ratios as high as 1200 pptv were observed in plumes that originated to the east over land. CH2O observations were consistently higher than the results from a point model constrained by other photochemical species and meteorological parameters. Regardless of latitude or longitude, agreement was best at altitudes above 4 km where the difference between measured and modeled CH2O medians was less than 50 pptv. Below 2 km the model median was approximately 150 pptv less than the measured median. Copyright 2001 by the American Geophysical Union.

Relationships and variability of bio-optical properties in coastal waters are investigated. Optical proxies indicate that these coastal waters are optically complex and highly variable and are categorized as follows: (1) relatively clear and dominated by high index of refraction, biogenic particles, (2) more turbid, consisting of mostly inorganic particles and little phytoplankton, (3) extremely turbid with high concentrations of inorganic particles, and (4) more turbid and dominated by biogenic particles. We present a method, alternative to traditional remote-sensing algorithms, of classifying coastal waters [the Spectral Angle Mapper (SAM)] and utilize the SAM to successfully isolate plume conditions in time series of downwelling irradiance and total absorption coefficient. We conclude with a discussion of the use of the SAM for coastal management operations. OCIS codes: 010.4450, 280.0280.

Background Kidney injury molecule-1 (KIM-1) has been associated with kidney damage in patients with preexisting renal disease. However, little is known about the relationships of KIM-1 with renal function and cardiovascular risk factors in healthy individuals from the general population. Methods Healthy individuals aged 25–41 years were enrolled in a population-based study. Main exclusion criteria were a BMI > 35 kg/m 2 , preexisting kidney disease or established cardiovascular disease. KIM-1 was measured from frozen plasma samples using a high-sensitivity assay. Multivariable linear regression models were constructed to assess the relationships of KIM-1 with renal function and various cardiovascular risk factors. Results We included 2060 individuals (47% men, median (interquartile range) age: 37 (31–40) years) in this analysis. Median KIM-1 levels were 82.5 (IQR 59.4–112.7) pg/ml. We found no significant relationship of KIM-1 with creatinine (adjusted β-coefficient (95% confidence interval) 0.0005 (− 0.002; 0.003), p = 0.61) and cystatin C (− 0.02 (− 0.21; 0.17), p = 0.84). There were significant linear relationships of log-transformed KIM-1 with systolic blood pressure (adjusted β-coefficient (95% confidence interval) 0.07 (0.04; 0.09), p < 0.0001), diastolic blood pressure (0.04 (0.02; 0.07), p = 0.001), low-density lipoprotein cholesterol (0.09 (0.06; 0.11), p < 0.0001), high-density lipoprotein cholesterol (0.07 (0.05; 0.1), p < 0.0001), high-sensitivity C-reactive protein (0.05 (0.03; 0.07), p < 0.0001), age (0.09 (0.07; 0.11), p < 0.0001), BMI (0.04 (0.01; 0.06), p = 0.005) and current smoking (0.12 (0.07; 0.17), p < 0.0001). Conclusion Among healthy adults from the general population, plasma levels of KIM-1 were not associated with renal function but were independently related to multiple cardiovascular risk factors. [ABSTRACT FROM AUTHOR]