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We have performed an analysis of reprocessed GPS/MET data spanning 1995–1997 generated by the COSMIC Data Analysis and Archive Center (CDAAC) in 2007. CDAAC developed modified dual-frequency processing methods for the encrypted data (anti-spoofing (AS)-on) during 1995–1997. We compared the CDAAC data set to the Modern-Era Retrospective Analysis for Research and Applications-2 (MERRA-2) reanalysis, separately for AS-on and AS-off, focusing on the altitude range 10–30 km. MERRA-2 did not assimilate GPS/MET data in the period 1995–1997. To gain insight into the CDAAC data set, we developed a single-frequency data set for GPS/MET, which is unaffected by the presence of encryption. We find excellent agreement between the more limited single-frequency data set and the CDAAC data set: the bias between these two data sets is consistently less than 0.25 % in refractivity, whether or not AS is on. Given the different techniques applied between the CDAAC and the new data set presented here (designated JPL), agreement suggests that the CDAAC AS-on processing and the single-frequency processing are not biased in an aggregate sense greater than 0.25 % in refractivity, which corresponds approximately to a temperature bias less than 0.5 K. Since the profiles contained in the new single-frequency data set are not a subset of the CDAAC profiles, the combination of the CDAAC data set, consisting of 9579 profiles, and the new single-frequency data set, consisting of 4729 profiles, yields a total number of 11 531 unique profiles from combining the JPL and CDAAC data sets. All numbers are after quality control has been applied by the respective processing activities.

We examined the longitudinal impact of self-reported exposure to pro- and anti-tobacco media on adolescents' susceptibility to smoking, using in-school surveys from a culturally diverse sample. Ethnicity and acculturation also were examined as potential moderators. Middle-school students (N = 2,292) completed self-report questionnaires during the 6th, 7th, and 8th grades. Chi-square analyses were conducted to determine whether reported exposure to pro- and anti-tobacco media varied according to ethnicity, acculturation, and immigration status. Logistic regression models were used to examine whether pro- and anti-tobacco media exposure in 6th grade was associated with susceptibility to smoking by later grades. Recall of people smoking in television programs and pro-tobacco advertisements in stores was associated with adolescent smoking susceptibility. Exposure to anti-tobacco advertisements on television protected against susceptibility. No significant interaction effects between pro- and anti-tobacco media exposure on smoking susceptibility were found. Ethnicity and acculturation did not moderate these associations. Our longitudinal study provides evidence that pro-tobacco media and advertising increases susceptibility to smoking over time. More important, anti-tobacco advertisements are not sufficient to reduce the harmful effects of adolescent exposure to pro-tobacco media. Policy-level interventions such as restrictions in tobacco advertising may be necessary to prevent adolescent smoking.

A series of covariance analyses is presented for the Navy's Geosat Follow-On (GFO) altimetric satellite using selective availability/anti-spoof (SA/A-S) qualified (dual frequency) and non-SA/A-S qualified (single frequency) GPS receiver configurations. Data obtained indicate that a SA/A-S qualified GPS receiver is capable of meeting the 10 cm GFO post-processed radial orbit accuracy requirement when using reduced dynamic tracking. The non-SA/A-S qualified receiver is also capable of approaching this 10 cm radial uncertainty level if all systematic errors are removed from the C/A pseudorange and reduced dynamic tracking is used again.