Multiannual observations of acetone, methanol, and acetaldehyde in remote tropical atlantic air: implications for atmospheric OVOC budgets and oxidative capacity.

Oxygenated volatile organic compounds (OVOCs) in the atmosphere are precursors to peroxy acetyl nitrate (PAN), affect the tropospheric ozone budget, and in the remote marine environment represent a significant sink of the hydroxyl radical (OH). The sparse observational database for these compounds, particularly in the tropics, contributes to a high uncertainty in their emissions and atmospheric significance. Here, we show measurements of acetone, methanol, and acetaldehyde in the tropical remote marine boundary layer made between October 2006 and September 2011 at the Cape Verde Atmospheric Observatory (CVAO) (16.85° N, 24.87° W). Mean mixing ratios of acetone, methanol, and acetaldehyde were 546 ± 295 pptv, 742 ± 419 pptv, and 428 ± 190 pptv, respectively, averaged from approximately hourly values over this five-year period. The CAM-Chem global chemical transport model reproduced annual average acetone concentrations well (21% overestimation) but underestimated levels by a factor of 2 in autumn and overestimated concentrations in winter. Annual average concentrations of acetaldehyde were underestimated by a factor of 10, rising to a factor of 40 in summer, and methanol was underestimated on average by a factor of 2, peaking to over a factor of 4 in spring. The model predicted summer minima in acetaldehyde and acetone, which were not apparent in the observations. CAM-Chem was adapted to include a two-way sea-air flux parametrization based on seawater measurements made in the Atlantic Ocean, and the resultant fluxes suggest that the tropical Atlantic region is a net sink for acetone but a net source for methanol and acetaldehyde. Inclusion of the ocean fluxes resulted in good model simulations of monthly averaged methanol levels although still with a 3-fold underestimation in acetaldehyde. Wintertime acetone levels were better simulated, but the observed autumn levels were more severely underestimated than in the standard model. We suggest that the latter may be caused by underestimated terrestrial biogenic African primary and/or secondary OVOC sources by the model. The model underestimation of acetaldehyde concentrations all year round implies a consistent significant missing source, potentially from secondary chemistry of higher alkanes produced biogenically from plants or from the ocean. We estimate that low model bias in OVOC abundances in the remote tropical marine atmosphere may result in up to 8% underestimation of the global methane lifetime due to missing model OH reactivity. Underestimation of acetaldehyde concentrations is responsible for the bulk (∼70%) of this missing reactivity.

Nitrogen management is essential to prevent tropical oil palm plantations from causing ground-level ozone pollution.

More than half the world's rainforest has been lost to agriculture since the Industrial Revolution. Among the most widespread tropical crops is oil palm (Elaeis guineensis): global production now exceeds 35 million tonnes per year. In Malaysia, for example, 13% of land area is now oil palm plantation, compared with 1% in 1974. There are enormous pressures to increase palm oil production for food, domestic products, and, especially, biofuels. Greater use of palm oil for biofuel production is predicated on the assumption that palm oil is an "environmentally friendly" fuel feedstock. Here we show, using measurements and models, that oil palm plantations in Malaysia directly emit more oxides of nitrogen and volatile organic compounds than rainforest. These compounds lead to the production of ground-level ozone (O(3)), an air pollutant that damages human health, plants, and materials, reduces crop productivity, and has effects on the Earth's climate. Our measurements show that, at present, O(3) concentrations do not differ significantly over rainforest and adjacent oil palm plantation landscapes. However, our model calculations predict that if concentrations of oxides of nitrogen in Borneo are allowed to reach those currently seen over rural North America and Europe, ground-level O(3) concentrations will reach 100 parts per billion (10(9)) volume (ppbv) and exceed levels known to be harmful to human health. Our study provides an early warning of the urgent need to develop policies that manage nitrogen emissions if the detrimental effects of palm oil production on air quality and climate are to be avoided.

Measurement and modelling of air pollution and atmospheric chemistry in the U.K. West Midlands conurbation: overview of the PUMA Consortium project.

The PUMA (Pollution of the Urban Midlands Atmosphere) Consortium project involved intensive measurement campaigns in the Summer of 1999 and Winter of 1999/2000, respectively, in which a wide variety of air pollutants were measured in the UK West Midlands conurbation including detailed speciation of VOCs and major component analysis of aerosol. Measurements of the OH and HO2 free radicals by the FAGE technique demonstrated that winter concentrations of OH were approximately half of those measured during the summer despite a factor of 15 reduction in production through the photolysis of ozone. Detailed box modelling of the fast reaction chemistry revealed the decomposition of Criegee intermediates formed from ozone-alkene reactions to be responsible for the majority of the formation of hydroxyl in both the summer and winter campaigns, in contrast to earlier rural measurements in which ozone photolysis was predominant. The main sinks for hydroxyl are reactions with NO2, alkenes and oxygenates. Concentrations of the more stable hydrocarbons were found to be relatively invariant across the conurbation, but the impacts of photochemistry were evident through analyses of formaldehyde which showed the majority to be photochemical in origin as opposed to emitted from road traffic. Measurements on the upwind and downwind boundaries of the conurbation revealed substantial enhancements in NOx as a result of emissions within the conurbation, especially during westerly winds which carried relatively clean air. Using calcium as a tracer for crustal particles, it proved possible to reconstruct aerosol mass from the major chemical components with a fairly high degree of success. The organic to elemental carbon ratios showed a far greater influence of photochemistry in summer than winter, presumably resulting mainly from the greater availability of biogenic precursors during the summer campaign. Two urban airshed models were developed and applied to the conurbation, one Eulerian, the other Lagrangian. Both were able to give a good simulation of concentrations of both primary and secondary pollutants at urban background locations.

Presymptomatic testing for adult onset polycystic kidney disease in at-risk kidney transplant donors.

Autosomal dominant adult-onset polycystic kidney disease (ADPKD) is estimated to have an incidence of 1/1,000 and accounts for approximately 10% of all end-stage renal disease in the United States. While relatives are attractive as renal donors due to their availability and the improved transplant success associated with living-related donors, they may coincidentally be at risk for ADPKD. Accurate presymptomatic testing for at-risk potential donors is critical for both the donor and the recipient. We report here 2 families in which presymptomatic testing for ADPKD was accomplished by DNA linkage analysis on several potential renal donors prior to transplant. This resulted in the protection of both donors and recipients by preventing the transplantation of a kidney affected by ADPKD. Thorough counseling prior to DNA analysis (including discussion of accuracy and possible testing outcomes of presymptomatic diagnosis of ADPKD, diagnosis of noncarrier status, false paternity, and non-informative study) was essential to provide informed consent and preserve confidentiality within the family. Confidentiality for potential donors found presymptomatically to be affected (with a 94% or greater probability) was especially difficult to maintain.

Anticipating and addressing workplace static magnetic field effects at levels <0.5 mT.

Magnetic resonance, once a research tool limited to the basic sciences, has experienced an increase in popularity due to its unique ability to analyze certain living systems in vivo. Expanding applications in the biomedical sciences have resulted in magnetic sources being located in research institutions nationally. Space and resource limitations sometimes necessitate siting magnetic resonance units in proximity to other institutional operations. For magnetic field shielding and personnel protection considerations, the generally accepted 0.5 mT (milliTesla) limit for implanted cardiac devices is commonly used as the conservative basis for decisions. But the effects of magnetic fields on equipment can be easily observed at levels far below 0.5 mT, often resulting in concern and apprehension on the part of personnel in the surrounding areas. Responding to recurrent worker concerns spawned by noticeable effects on equipment at exposure levels <0.5 mT can strain finite radiation safety program resources. To enhance the ability to anticipate possible facility incompatibility issues associated with the installation of magnetic sources, a literature review was conducted to summarize documented equipment effects. Various types of equipment were found to be impacted at levels ranging down to perhaps 0.001 mT. Armed with this information, practicing radiation safety professionals can better anticipate facility incompatibility issues and improve their responses to worker concerns initiated by observed effects on equipment.

Family practice residency graduates as faculty members.

The demand for teachers of family practice is being met in part by recent residency graduates. The background of these individuals would not predict that they would become teachers, and a major role adaptation is required of them. Yet a number of factors lead them to elect to become faculty members. They possess several qualities different from faculty members coming from practice backgrounds and are, therefore, able to make unique contributions. A combination of recent graduates and practice-experienced faculty members may represent the ideal mix for the further development of academic family practice.

Experience of family practice residents as athletic team physicians.

Providing exposure for family practice residence to all aspects of community medicine is a common goal of training programs. The Antelope Valley Hospital Medical Center Family Practice Program has initiated an innovative project which involves residents serving as team physicians for local college athletic teams. This provides a valuable opportunity for residents to learn skills they can be expected to need in their future practice. The team physician's role offers educational potential for family practice residents through experience with acute orthopedic problems as well as the preventive and psychological aspects of sports medicine. This role also serves as an example of physician responsibility for health-related activities in the acommunity.

The atmospheric chemistry of trace gases and particulate matter emitted by different land uses in Borneo.

We report measurements of atmospheric composition over a tropical rainforest and over a nearby oil palm plantation in Sabah, Borneo. The primary vegetation in each of the two landscapes emits very different amounts and kinds of volatile organic compounds (VOCs), resulting in distinctive VOC fingerprints in the atmospheric boundary layer for both landscapes. VOCs over the Borneo rainforest are dominated by isoprene and its oxidation products, with a significant additional contribution from monoterpenes. Rather than consuming the main atmospheric oxidant, OH, these high concentrations of VOCs appear to maintain OH, as has been observed previously over Amazonia. The boundary-layer characteristics and mixing ratios of VOCs observed over the Borneo rainforest are different to those measured previously over Amazonia. Compared with the Bornean rainforest, air over the oil palm plantation contains much more isoprene, monoterpenes are relatively less important, and the flower scent, estragole, is prominent. Concentrations of nitrogen oxides are greater above the agro-industrial oil palm landscape than over the rainforest, and this leads to changes in some secondary pollutant mixing ratios (but not, currently, differences in ozone). Secondary organic aerosol over both landscapes shows a significant contribution from isoprene. Primary biological aerosol dominates the super-micrometre aerosol over the rainforest and is likely to be sensitive to land-use change, since the fungal source of the bioaerosol is closely linked to above-ground biodiversity.

An observational case study of ozone and precursors inflow to South East England during an anticyclone.

Summertime photochemical air pollution episodes within the United Kingdom have been proposed via modelling studies to be strongly influenced by regional scale inflow of air from the continental European boundary layer. We present a vertically resolved case study using measurements made from the NERC/Met Office BAe 146 research aircraft on 18th August 2005 over the South East of England and the North Sea during a weak anticyclone centred over Northern Europe. The vertical distribution of ozone, CO, NO(x), peroxyacetyl nitrate (PAN) and a wide range of both nonmethane hydrocarbons (NMHC) and oxygenated volatile organic compounds (OVOCs) were determined between 500 ft (approximately 152 m) and 7000 ft (approximately 2134 m) over the East Anglia coastline and 50 km inland. In excess of 80 ppbV ozone was observed within inflowing boundary layer air over the North Sea coast in a broad N-S sloping feature around 60 km wide. The inflowing feature of European origin was also observed further inland within the boundary layer albeit with lower, more variable, ozone mixing ratios. The increased variability in ozone over land was a product of titration by fresh surface emissions of NO via rapid upward transport in thermals, a hypothesis supported by the observed vertical wind speed component. Fast boundary layer mixing over land was further illustrated by a uniform distribution in reactive alkenes. A comparison between aircraft and surface O(3) UK AUN (Automatic Urban Network) measurements showed good agreement with the inland site, Sibton, but marked differences with the coastal monitoring site at Weybourne, potentially due to gradients established by ocean deposition in stably stratified marine air.

Financial incentives for ambulatory care performance improvement.

BACKGROUND: Measuring and improving the quality of care while curtailing costs are essential objectives in capitated care. As patient care moves from the hospital to outpatient settings, quality management resources must be shifted to ambulatory care process improvement. The Quality Improvement and Efficiency Financial Incentives Program at Stanford University Medical Center was adopted to increase quality improvement efforts and contain costs. THE INCENTIVE PROGRAM: Each department's budget for care of capitated patients was reduced by 5% from the previous year. Return of a reserve fund (10% of payments for specialty care) required completion of substantive quality improvement projects and containing costs. Successful departments were also eligible for bonus funds. Implementation strategies included endorsement by clinical leaders, physician education, use of administrative data to identify project topics and support measurement of quality and cost variables, project templates and time lines, and the availability of clinical quality managers with special expertise in clinical process improvement. RESULTS: Eight of 13 clinical departments developed and implemented 19 ambulatory quality improvement projects to varying degrees. Success in the program was roughly correlated with the potential impact of the incentive on revenues and the status of the lead person selected by the department to spearhead their efforts. Only 5 departments achieved their cost containment goals. DISCUSSION: Financial incentives are one method of encouraging physicians to use clinical process improvement methods. Endorsement by clinical leaders and selection of realistic beginning projects enhance chances for success. The capitated population has attributes that make it an attractive focus for initial quality improvement efforts.

Measurements of C6-C8 hydrocarbons at a UK rural site during January 1999. Site evaluation and correlations between species.

Ambient concentrations of C6-C8 aromatic hydrocarbons and n-heptane, determined by gas chromatography with flame ionisation detection, are presented from a winter campaign during January 1999 at a rural site near Leeds. Absolute concentrations are significantly lower than those obtained from the only designated UK rural site (Harwell) in the automated UK hydrocarbon network. Both absolute and relative concentrations of hydrocarbons measured at the site have been interpreted in terms of the arriving back-trajectories. The site is subject to two main airflows during the winter months; relatively polluted air from the southwest and much cleaner air from the northwest. Ratios of hydrocarbon concentrations show evidence of significant chemical processing consistent with chemical removal by OH. Uncertainties in the ages of the trajectories prevent a reliable estimation of the average OH concentration over the trajectory. The dependence of the variance of the hydrocarbon concentrations with their lifetime with respect to removal by OH does not show the expected behaviour.

Infant responsivity to curvature.

The reactions of 112 10-month-old male infants to the property of curvature were examined using a habituation paradigm with lever pressing as an instrumental response. 4 levels of curvature (straightt line, minimal curve, moderate curve, large curve) each served as a standard (habituation) stimulus and as a transformation stimulus in 9 separate experimental conditions. Results revealed a greater initial dishabituation of reinforced instrumental responding in those conditions crossing the curved/straight boundary; furthermore, this initial dishabituation was sustained throughout the transformation phase of the experiment in those conditions which involved changes from straight to curved, but not curved to straight. Results are interpreted as implying a special attention-recruiting value for curvature in 10-month old infants.