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Results of the study are promising in at least 2 ways: (1) a multimodal inpatient program might stop the negative effects of chronic pain, disability, and emotional distress in children and adolescents, and (2) the exploration of clinical significance testing has demonstrated utility and can be applied to future effectiveness studies in pediatric pain.

The objective of this study was to measure ammonia (NH3) emissions from modern technology vehicles since information is scarce aboutthis importantsource of particulate matter (PM) precursors. Test variables included the emission level to which the vehicle was certified, the vehicle operating conditions, and catalyst age. Eight vehicles with low-emission vehicle (LEV) to super-ultralow-emission vehicle (SULEV) certification levels were tested over the Federal Test Procedure (FTP75), a US06 cycle, a hot running 505, a New York City Cycle (NYCC), and a specially designed Modal Emissions Cycle (MEC01v7) using both as-received and bench-aged catalysts. NH3 emissions in the raw exhaust were measured by tunable diode laser (TDL) absorption spectroscopy. The results show that NH3 emissions depend on driving mode and are primarily generated during acceleration events. More specifically, high NH3 emissions were found for high vehicle specific power (VSP) events and rich operating conditions. For some vehicles, NH3 emissions formed immediately after catalyst light-off during a cold start.

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A pulse radiolysis technique was used to measure the UV absorption spectra of c-C3H5O3(•) and (c-C3H5O3)O2(•) radicals over the range 220−300 nm, with σ(c-C3H5O3(•))250 nm = (5.2 ± 0.7) × 10-18 and σ((c-C3H5O3)O2(•))250 nm = (3.7 ± 0.4) × 10-18 cm2 molecule-1. The self-reaction rate constant for the c-C3H5O3(•) radicals, defined as d[c-C3H5O3(•)]/dt = 2k 4[c-C3H5O3(•)]2, was k 4 = (3.1 ± 0.6) × 10-11 cm3 molecule-1 s-1. The rate constants for reactions of (c-C3H5O3)O2(•) radicals with NO and NO2 were k 6 = (5.8 ± 1.4) × 10-12 and k 7 = (1.1 ± 0.2) × 10-11 cm3 molecule-1 s-1, respectively. The rate constants for the reaction of F atoms with 1,3,5-trioxane and the reaction of c-C3H5O3(•) radicals with O2 were k 3 = (1.1 ± 0.4) × 10-10 and k 2 = (7.4 ± 1.1) × 10-12 cm3 molecule-1 s-1, respectively. Relative rate techniques were used to measure the rate constants for the reactions of OH radicals and Cl atoms with 1,3,5-trioxane and Cl atoms with H(O)COCH2OC(O)H, k 20 = (6.0 ± 1.0) × 10-12, k 24 = (1.0 ± 0.2) × 10-10, and k 25 = (5.1 ± 1.0) × 10-13 cm3 molecule-1 s-1, respectively. FTIR−smog chamber systems were used to show that the atmospheric fate of the alkoxy radical (c-C3H5O3)O(•) is decomposition via C−O bond scission leading to the formation of H(O)COCH2OC(O)H (methylene glycol diformate). The IR spectrum of the peroxynitrate (c-C3H5O3)O2NO2 is presented. The results are discussed with respect to the atmospheric chemistry of 1,3,5-trioxane.