The Role of Convection in Redistributing Formaldehyde to the Upper Troposphere Over North America and the North Atlantic during the Summer 2004 INTEX Campaign

Measurements of CH2O from a tunable diode laser absorption spectrometer (TDLAS) were acquired onboard the NASA DC-8 during the summer 2004 INTEX-NA (Intercontinental Chemical Transport Experiment - North America) campaign to test our understanding of convection and production mechanisms in the upper troposphere (UT, 6-12-km) over continental North America and the North Atlantic Ocean. Point-by-point comparisons with box model calculations, when MHP (CH3OOH) measurements were available for model constraint, resulted in a median CH2O measurement/model ratio of 0.91 in the UT. Multiple tracers were used to arrive at a set of UT CH2O background and perturbed air mass periods, and 46% of the TDLAS measurements fell within the latter category. At least 66% to 73% of these elevated UT observations were caused by enhanced production from CH2O precursors rather than direct transport of CH2O from the boundary layer. This distinction is important, since the effects from the former can last for over a week or more compared to one day or less in the case of convective transport of CH2O itself. In general, production of CH2O from CH4 was found to be the dominant source term, even in perturbed air masses. This was followed by production from MHP, methanol, PAN type compounds, and ketones, in descending order of their contribution. In the presence of elevated NO from lightning and potentially from the stratosphere, there was a definite trend in the CH2O discrepancy, which for the highest NO mixing ratios produced a median CH2O measurement/model ratio of 3.9 in the 10-12-km range. Discrepancies in CH2O and HO2 in the UT with NO were highly correlated and this provided further information as to the possible mechanism(s) responsible. These discrepancies with NO are consistent with additional production sources of both gases involving CH3O2 + NO reactions, most likely caused by unmeasured hydrocarbons

Formaldehyde over North America and the North Atlantic during the summer 2004 INTEX campaign: Methods, observed distributions, and measurement‐model comparisons

A tunable diode laser absorption spectrometer (TDLAS) was operated on the NASA DC‐8 aircraft during the summer INTEX‐NA study to acquire ambient formaldehyde (CH2O) measurements over North America and the North Atlantic Ocean from ∼0.2 km to ∼12.5 km altitude spanning 17 science flights. Measurements of CH2O in the boundary layer and upper troposphere over the southeastern United States were anomalously low compared to studies in other years, and this was attributed to the record low temperatures over this region during the summer of 2004. Formaldehyde is primarily formed over the southeast from isoprene, and isoprene emissions are strongly temperature‐dependent. Despite this effect, the median upper tropospheric (UT) CH2O mixing ratio of 159 pptv from the TDLAS over continental North America is about a factor of 4 times higher than the median UT value of 40 pptv observed over remote regions during TRACE‐P. These observations together with the higher variability observed in this study all point to the fact that continental CH2O levels in the upper troposphere were significantly perturbed during the summer of 2004 relative to more typical background levels in the upper troposphere over more remote regions. The TDLAS measurements discussed in this paper are employed together with box model results in the companion paper by Fried et al. to further examine enhanced CH2O distributions in the upper troposphere due to convection. Measurements of CH2O on the DC‐8 were also acquired by a coil enzyme fluorometric system and compared with measurements from the TDLAS system

057 Epifluorescent and light microscopic visualization of bacterial microcolonies in acute wound infections – Are these biofilms?

A biofilm is a formation of surface‐associated microbial cells that are enclosed in a self produced extracellular polymeric substance matrix. This definition is acceptable for in‐vitro research but a clear definition for biofilm‐associated diseases has yet to be elucidated. A structural/morphological definition is currently used to define biofilms; additionally, physiological or molecular criteria will allow us to define biofilms in disease infection accurately. Our objective over the past several years has been to characterize and observe bacterial biofilms in wound infections using different wound models. To broaden our current understanding of biofilm morphology in wounds for this study we used epifluorescent and light microscopy to visualize wound pathogenic pseudomonas aeruginosa bacteria in a porcine partial thickness infection model. Three experimental animals were used for this study. After animal preparation, partial thickness wounds were created on the backs of 3 animals. Wounds were then inoculated with 106 colony forming units/ml (CFU/ml) of Pseudomonas aeruginosa and covered for 48 hours to allow bacteria to colonize and infect the wound. Biopsies were obtained from normal skin, wounds before inoculation, wounds at 48 hours and wounds 48 hours after inoculation. Biopsies were processed and stained with Hematoxylin and Eosin for light microscopy and Calcofluor White and Ethidium Bromide for epifluorescence microscopy. Images obtained using epifluorescent and light microscopy demonstrate that bacteria form aggregates of microcolonies. These structures are representative of bacterial biofilms and support the hypothesis that bacteria live as biofilms in wound infection. Although currently there is no established and accepted definition for biofilm associated diseases, we anticipate that more studies looking into physiological changes of these structures will clarify our current understanding of wound infection and treatment

The incidence of recurrent herpes simplex and herpes zoster infection during treatment with arsenic trioxide

We report the incidence of varicella zoster virus (VZV) and herpes simplex virus (HSV) infection in patients with multiple myeloma and colon cancer who were treated with arsenic trioxide for their disease. In this report, we discuss the effects of arsenic on immune system, and suggest arsenic compounds as a possible predisposing factor for viral reactivation in these patients

Kinetics of iminium ion catalysis

To a stirred solution of cinnamaldehyde (118 mg, 1.42 mmol, 122 ?l) in methanol (2ml), trifluoromethylpyrrolidine (198 mg, 1.42 mmol) was added and allowed to stir at ambient temperature for 2 minutes. After this time, hexafluorophosphoric solution in H2O (60% w/w) (345 mg, 1.42 mmol, 210 ?l) was added which immediately formed a yellow precipitate on addition. The excess solvent was removed in vacuo and the crude mixture was recrystallised from hot methanol to give 6 (493 mg, 87%) as an off white solid; mp 199-201 oC; ?max(Nujol) 2923, 2853, 1621, 1591, 1456, 1376 cm-1; 1H NMR (400MHz, CD3CN) ? 8.64 (d, J = 10.6 Hz, 1H), 8.12 (d, J = 15.2 Hz, 1H), 7.91-7.89 (m, 2H), 7.69-7.67 (m, 1H), 7.60-7.57 (m, 2H), 7.32 (dd, J = 10.6Hz, 15.2Hz, 1H), 5.0-4.96 (m, 1H), 4.24-4.14 (m, 2H), 2.52-2.45 (m, 1H), 2.42-2.27 (m, 3H); 13C NMR (125 MHz, CDCl3) ? 170.8, 165.3, 134.9, 131.2, 129.7, 125.1, 118.4, 66.8 (q, J1CF = 31.3 Hz), 53.3, 24.9, 22.6, 21.7; m/z (APCI) 254 [M–PF6]?+; HRMS (ES) found 254.1152 [M–PF6].+; calculated for C14H15NF3 254.1151