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AIM To assess in a cross-sectional clinical study the effect of antibiotics on the diversity, structure and metabolic pathways of bacterial communities in various oral environments in patients with acute primary infections. METHODOLOGY Samples of saliva (SA), supragingival biofilm (SB) and from the pulp cavity (PC) were collected from teeth with acute primary infections and then grouped according to previous use of antibiotics (NoAtb = no antibiotics [n = 6]; Atb = antibiotics [n = 6]). DNA sequencing was conducted using MiSeq (Illumina, San Diego, CA, USA). The V1-V3 hyper-variable region of the 16S rRNA gene was amplified. A custom Mothur pipeline was used for 16S rRNA processing. Subsequent analyses of the sequence dataset were performed in R (using vegan, phyloseq and ggplot2 packages) or QIIME. RESULTS Twelve patients aged from 22 to 56 years were recruited. Participants in the Atb group had taken the beta-lactamics amoxicillin (5/6) or cephalexin (1/6) for 2-3 days. A total of 332 bacterial taxa (OTUs) were identified, belonging to 120 genera, 60 families and nine phyla. Firmicutes (41%) and Bacteroidetes (38%) were the most abundant phyla in all samples. Taxa clustered significantly by oral site (PCoA analysis; P

This study analyzes seasonal and spatial patterns of column carbon dioxide (CO2) over North America, calculated from aircraft and tall tower measurements from the NOAA Global Greenhouse Gas Reference Network from 2004 to 2014. Consistent with expectations, gradients between the eight regions studied are larger below 2 km than above 5 km. The 11-year mean CO2 dry mole fraction (XCO2) in the column below ∼ 330 hPa ( ∼ 8 km above sea level) from NOAA's CO2 data assimilation model, CarbonTracker (CT2015), demonstrates good agreement with those calculated from calibrated measurements on aircraft and towers. Total column XCO2 was attained by combining modeled CO2 above 330 hPa from CT2015 with the measurements. We find large spatial gradients of total column XCO2 from June to August, with north and northeast regions having ∼ 3 ppm stronger summer drawdown (peak-to-valley amplitude in seasonal cycle) than the south and southwest regions. The long-term averaged spatial gradients of total column XCO2 across North America show a smooth pattern that mainly reflects the large-scale circulation. We have conducted a CarbonTracker experiment to investigate the impact of Eurasian long-range transport. The result suggests that the large summertime Eurasian boreal flux contributes about half of the north–south column XCO2 gradient across North America. Our results confirm that continental-scale total column XCO2 gradients simulated by CarbonTracker are realistic and can be used to evaluate the credibility of some spatial patterns from satellite retrievals, such as the long-term average of growing-season spatial patterns from satellite retrievals reported for Europe which show a larger spatial difference ( ∼ 6 ppm) and scattered hot spots.

In 2014, a satellite-based map of regional anomalies of atmospheric methane (CH4) column retrievals singled out the fossil fuel rich San Juan Basin (SJB) as the biggest CH4 regional anomaly (“hot spot”) in the United States. Over a 3-week period in April 2015, we conducted ground and airborne atmospheric measurements to investigate daily wind regimes and CH4 emissions in this region of SW Colorado and NW New Mexico. The SJB, similar to other topographical basins with local sources, experienced elevated surface air pollution under low wind and surface temperature inversion at night and early morning. Survey drives in the basin identified multiple CH4 and ethane (C2H6) sources with distinct C2H6-to-CH4 emission plume ratios for coal bed methane (CBM), natural gas, oil, and coal production operations. Air samples influenced by gas seepage from the Fruitland coal formation outcrop in La Plata County, CO, had enhanced CH4, with no C2-5 light alkane enhancements. In situ fast-response data from seven basin survey flights, all with westerly winds, were used to map and attribute the detected C2H6 and CH4 emission plumes. C2H6-to-CH4 plume enhancement correlation slopes increased from north to south, reflecting the composition of the natural gas and/or CBM extracted in different parts of the basin. Nearly 75% of the total detected CH4 and 85% of the total detected C2H6 hot spot were located in New Mexico. Emissions from CBM and natural gas operations contributed 66% to 75% of the CH4 hot spot. Emissions from oil operations in New Mexico contributed 5% to 6% of the CH4 hot spot and 8% to 14% of the C2H6 hot spot. Seepage from the Fruitland coal outcrop in Colorado contributed at most 8% of the total detected CH4, while gas venting from the San Juan underground coal mine contributed

Four quadrupole lenses based on permanent magnets of the NdFeB material (PMQ) were developed for the imaging section for forming images of the ion-optical system of the PRIOR proton microscope prototype: the effective length of two of them is 144 mm, and the other two are 288 mm long. The field induction at the radius of the lens aperture is 1.77 Т, and the aperture is 30 mm in size. The modular design of the PMQ makes it possible to vary the length of the lenses, compensate for the offset of the magnetic axis from the ion optical axis of the microscope channel, and decrease the variation of the angular position of the magnetic medians. The PMQ magnetic field was adjusted, scanned, and its main characteristics were determined. The 3D mathematical models of the magnetic-field distribution that are obtained as a result of PMQ measurements are intended for the use in calculations of the beam dynamics during adjustment of the ion-optical system of the proton microscope and for attaining the highest spatial resolution. The developed lenses were used in the first experiments on the PRIOR facility.

An intensive coordinated airborne and ground-based measurement study was conducted in the Fayetteville Shale in northwestern Arkansas during September and October 2015 to compare and explain potential discrepancies between top-down and bottom-up estimates of regional natural gas (NG) methane (CH4) emissions. In situ mobile downwind measurements are used to document the ethane to methane enhancement ratios (ERs) in emission plumes from NG operations in the region. Enhancement ratios are low (

Seasonal spatial and temporal gradients for the CO2 mole fraction over North America are examined by creating a climatology from data collected 2004–2013 by the NOAA/ESRL Global Greenhouse Gas Reference Network Aircraft Program relative to trends observed for CO2 at the Mauna Loa Observatory. The data analyzed are from measurements of air samples collected in specially fabricated flask packages at frequencies of days to months at 22 sites over continental North America and shipped back to Boulder, Colorado, for analysis. These measurements are calibrated relative to the CO2 World Meteorological Organization mole fraction scale. The climatologies of CO2 are compared to climatologies of CO, CH4, SF6, N2O (which are also measured from this sampling program), and winds to understand the dominant transport and chemical and biological processes driving changes in the spatial and temporal mole fractions of CO2 as air passes over continental North America. The measurements show that air masses coming off the Pacific on the west coast of North America are relatively homogeneous with altitude. As air masses flow eastward, the lower section from the surface to 4000 m above sea level (masl) becomes distinctly different from the 4000–8000 masl section of the column. This is due in part to the extent of the planetary boundary layer, which is directly impacted by continental sources and sinks, and to the vertical gradient in west-to-east wind speeds. The slowdown and southerly shift in winds at most sites during summer months amplify the summertime drawdown relative to what might be expected from local fluxes. This influence counteracts the dilution of summer time CO2 drawdown (known as the “rectifier effect”) as well as changes the surface influence “footprint” for each site. An early start to the summertime drawdown, a pronounced seasonal cycle in the column mean (500 to 8000 masl), and small vertical gradients in CO2, CO, CH4, SF6, and N2O at high-latitude western sites such as Poker Flat, Alaska, suggest recent influence of transport from southern latitudes and not local processes. This transport pathway provides a significant contribution to the large seasonal cycle observed in the high latitudes at all altitudes sampled. A sampling analysis of the NOAA/ESRL CarbonTracker model suggests that the average sampling resolution of 22 days is sufficient to get a robust estimate of mean seasonal cycle of CO2 during this 10 year period but insufficient to detect interannual variability in emissions over North America.

Emissions of methane (CH4) from oil and natural gas (O&G) operations in the most densely drilled area of the Denver-Julesburg Basin in Weld County located in northeastern Colorado are estimated for 2 days in May 2012 using aircraft-based CH4 observations and planetary boundary layer height and ground-based wind profile measurements. Total top-down CH4 emission estimates are 25.8 ± 8.4 and 26.2 ± 10.7 t CH4/h for the 29 and 31 May flights, respectively. Using inventory data, we estimate the total emissions of CH4 from non-O&G gas-related sources at 7.1 ± 1.7 and 6.3 ± 1.0 t CH4/h for these 2 days. The difference in emissions is attributed to O&G sources in the study region, and their total emission is on average 19.3 ± 6.9 t/h, close to 3 times higher than an hourly emission estimate based on Environmental Protection Agency's Greenhouse Gas Reporting Program data for 2012. We derive top-down emissions estimates for propane, n-butane, i-pentane, n-pentane, and benzene from our total top-down CH4 emission estimate and the relative hydrocarbon abundances in aircraft-based discrete air samples. Emissions for these five nonmethane hydrocarbons alone total 25.4 ± 8.2 t/h. Assuming that these emissions are solely originating from O&G-related activities in the study region, our results show that the state inventory for total volatile organic compounds emitted by O&G activities is at least a factor of 2 too low for May 2012. Our top-down emission estimate of benzene emissions from O&G operations is 173 ± 64 kg/h, or 7 times larger than in the state inventory.

Atmospheric CO were monitored at the Lulin Atmospheric Background Station (LABS) with an elevation of 2862 m AMSL from April 2006 to April 2011 by the in-situ non-dispersive infrared (NDIR) spectrometer and weekly flask sample collections via collaboration with NOAA/ESRL/GMD. In general very coherent results were observed between the two datasets, despite a slight difference between the two. A distinct seasonal pattern of CO was noticed at the LABS with a springtime maximum and a summertime minimum, which was predominately shaped by the long-range transport of biomass burning air masses from Southeast Asia and oceanic influences from the Pacific, respectively. Diurnal cycles were also observed at the LABS, with a maximum in late afternoon and a minimum in early morning. The daytime CO maximum was most likely caused by the up-slope transport of lower elevation air. After filtering out the possibly polluted data points from the entire dataset with a mathematic procedure, the mean background CO level at the LABS was assessed as 129.3 ± 46.6 ppb, compared to 149.0 ± 72.2 ppb prior to the filtering. The cluster analysis of the backward trajectories revealed six possible source regions, which shows that air masses originating from the Westerly Wind Zone were dominated in spring and winter resulting in higher CO concentrations. As a contrast, the oceanic influences from the Pacific were found mostly in summer, contributing a lower seasonal CO concentration throughout a year.

[1] Methane (CH4) emissions from natural gas production are not well quantified and have the potential to offset the climate benefits of natural gas over other fossil fuels. We use atmospheric measurements in a mass balance approach to estimate CH4 emissions of 55 ± 15 × 103 kg h−1 from a natural gas and oil production field in Uintah County, Utah, on 1 day: 3 February 2012. This emission rate corresponds to 6.2%–11.7% (1σ) of average hourly natural gas production in Uintah County in the month of February. This study demonstrates the mass balance technique as a valuable tool for estimating emissions from oil and gas production regions and illustrates the need for further atmospheric measurements to determine the representativeness of our single-day estimate and to better assess inventories of CH4 emissions.

[1] Methane (CH4), carbon dioxide (CO2), carbon monoxide (CO), and C2–C5 alkanes were measured throughout the Los Angeles (L.A.) basin in May and June 2010. We use these data to show that the emission ratios of CH4/CO and CH4/CO2 in the L.A. basin are larger than expected from population-apportioned bottom-up state inventories, consistent with previously published work. We use experimentally determined CH4/CO and CH4/CO2 emission ratios in combination with annual State of California CO and CO2 inventories to derive a yearly emission rate of CH4 to the L.A. basin. We further use the airborne measurements to directly derive CH4 emission rates from dairy operations in Chino, and from the two largest landfills in the L.A. basin, and show these sources are accurately represented in the California Air Resources Board greenhouse gas inventory for CH4. We then use measurements of C2–C5 alkanes to quantify the relative contribution of other CH4 sources in the L.A. basin, with results differing from those of previous studies. The atmospheric data are consistent with the majority of CH4 emissions in the region coming from fugitive losses from natural gas in pipelines and urban distribution systems and/or geologic seeps, as well as landfills and dairies. The local oil and gas industry also provides a significant source of CH4 in the area. The addition of CH4 emissions from natural gas pipelines and urban distribution systems and/or geologic seeps and from the local oil and gas industry is sufficient to account for the differences between the top-down and bottom-up CH4 inventories identified in previously published work.

Recently a new high energy proton microscopy facility PRIOR (Proton Microscope for FAIR) has been designed, constructed and successfully commissioned at GSI Helmholtzzentrum f\"ur Schwerionenforschung (Darmstadt, Germany). As a result of the experiments with 3.5-4.5 GeV proton beams delivered by the heavy ion synchrotron SIS-18 of GSI, 30 um spatial and 10 ns temporal resolutions of the proton microscope have been demostrated. A new pulsed power setup for studying properties of matter under extremes has been developed for the dynamic commissioning of the PRIOR facility. This paper describes the PRIOR setup as well as the results of the first static and dynamic proton radiography experiments performed at GSI., Comment: 9 pages, 13 figures, submitted to Review of Scientific Instruments

Chronic ischemia in patients with peripheral arterial disease (PAD) represents a common medical problem. Neuropathic changes and pain caused by chronic ischemia are often found in the lower extremities of these patients. Pain in patients with chronic critical limb ischemia fulfill the criteria of neuropathic pain. Diagnostic tools besides medical history and examination are questionnaires, quantitative sensory testing (QST) and measuring intraepidermal nerve fiber density (IENFD) when indicated. A pharmacological approach with non-opioids and opioids as well as antidepressive and anticonvulsive drugs (according to the recommendations for the therapy of neuropathic pain) seems to be indicated for treating painful ischemic neuropathy. Spinal cord stimulation (SCS) provides the best evidence for invasive procedures in treating chronic ischemic pain.

Protons having energies in the GeV range have been proposed as an alternative to Bragg-peak hadron therapy. This strategy reduces lateral scattering and overcomes uncertainties of particle range and relative biological effectiveness. GeV protons could additionally be used for targeting in image guided stereotactic radiosurgery. We experimentally demonstrated the potential of GeV protons for imaging of biological samples using E=0.8 GeV protons and the pRad setup at Los Alamos National Laboratory (LANL). In this setup, a system of magnetic lenses creates a point-to-point mapping from object to detector. This mapping compensates image blur due to lateral scattering inside the imaged (biological) object. We produced 2-dim proton radiographs of biological samples, an anthropomorphic phantom and performed simple dosimetry. High resolution tomographic reconstructions were derived from the 2-dim proton radiographs. Our experiment was performed within the framework of the PANTERA (Proton Therapy and Radiography) project. In the future, the proton microscope PRIOR (Proton Microscope for FAIR) located in the FAIR facility (Darmstadt), will focus on optimizing the technique for imaging of lesions implanted in animals and couple the irradiation with standard radiotherapy.

Molecular hydrogen (H2) has been measured since 1989 in air samples collected using a globally distributed sampling network. Time series from 50 locations are used to better define the distribution and recent changes of H2 in the remote lower troposphere. These data show that the globally averaged H2 mixing ratio between 1991 and 1996 was about 531±6 parts per billion (ppb). Hydrogen exhibited well-defined seasonal cycles in each hemisphere, with similar seasonal maxima (530–550 ppb). However, in the Northern Hemisphere the seasonal minimum was 70 ppb deeper than in the Southern Hemisphere (∼450 and 520 ppb, respectively), resulting in ∼3% more H2 in the south than in the north. With these data we have reevaluated the global H2 budget. Methane oxidation is the largest source of H2 to the troposphere, and soil uptake accounts for much of its sink. The global annual turnover is estimated as ∼75 Tg H2 yr−1. The annual turnover, combined with a calculated tropospheric burden of 155 Tg, indicates a lifetime of ∼2 years. While our understanding of the global distribution of the sources and sinks of H2 is still incomplete, the lower annual minimum in the north may be reasonably attributed to hemispheric asymmetry in uptake by soils. The seasonal cycles in the two hemispheres show unusual similarities: the northern and the southern seasonal maxima and minima were offset by only a few months. We suggest that the seasonal cycle in the Southern Hemisphere is dominated by H2 emissions from biomass burning.

Since 1988, the distribution of carbon monoxide (CO) in the lower troposphere has been determined using a globally distributed air sampling network. Site locations range from 82°N to 90°S, with wide longitudinal coverage, and represent the marine boundary layer, regionally polluted atmospheres, and the free troposphere. These measurements present a unique, intercalibrated, and internally consistent data set that are used to better define the global temporal and spatial distribution of CO. In this paper, times series from 49 sites are discussed. With an average lifetime of ∼2 months, CO showed significant concentration gradients. In the marine boundary layer, mixing ratios were greatest in the northern winter (200-220 ppb) and lowest in the southern summer (35-45 ppb). The interhemispheric gradient showed strong seasonality with a maximum difference between the high latitudes of the northern and southern hemispheres (160-180 ppb) in February and March and a minimum in July and August (10-20 ppb). Higher CO was found in regions near human development relative to those over more remote areas. The distributions provide additional evidence of the widespread pollution of the lower atmosphere. Remote areas in the high northern hemisphere are polluted by anthropogenic activities in the middle latitudes, and those in the southern hemisphere are heavily influenced by the burning of biomass in the tropics. While tropospheric concentrations of CO exhibit periods of increase and decrease, the globally averaged CO mixing ratio over the period from 1990 through 1995 decreased at a rate of approximately 2 ppb yr -1 .

The global atmospheric methane burden has more than doubled since pre-industrial times1,2, and this increase is responsible for about 20% of the estimated change in direct radiative forcing due to anthropogenic greenhouse-gas emissions. Research into future climate change and the development of remedial environmental policies therefore require a reliable assessment of the long-term growth rate in the atmospheric methane load. Measurements have revealed that although the global atmospheric methane burden continues to increase2 with significant interannual variability3,4, the overall rate of increase has slowed2,5. Here we present an analysis of methane measurements from a global air sampling network that suggests that, assuming constant OH concentration, global annual methane emissions have remained nearly constant during the period 1984–96, and that the decreasing growth rate in atmospheric methane reflects the approach to a steady state on a timescale comparable to methane's atmospheric lifetime. If the global methane sources and OH concentration continue to remain constant, we expect average methane mixing ratios to increase slowly from today's 1,730 nmol mol−1 to ∼1,800 nmol mol−1, with little change in the contribution of methane to the greenhouse effect.

Wall created the term preemptive analgesia in 1988 and in doing so set in motion a movement to prevent acute and chronic postsurgical pain. The concept of preemptive analgesia implies the administration of analgesic drugs or an intervention before a surgical procedure. A preemptive analgesic approach can comprise non-steroidal anti-inflammatory drugs (NSAID) and cyclo-oxygenase-2 inhibitors (coxibs) used to decrease the production of prostaglandins, local anesthetics (e.g. epidural) to reduce nociceptive input to the spinal cord as well as opioids, N-methyl-D-aspartate (NMDA) antagonists, antidepressants and anticonvulsants, all of which have an inhibitory influence on the central nervous system.The aim of this article is to present the current possibilities and limits of preoperative pain therapy.Since 2002 several meta-analyses on the effectiveness of preemptive analgesia have been published which came to varying conclusions on the supportive use of preemptive analgesia. The S3 guidelines on current perioperative pain management developed by the German Interdisciplinary Association for Pain Management (DIVS) specify the preemptive analgesic interventions found to be effective and will be discussed in detail in this article. Furthermore, the results of a current meta-analysis which follows the principle of preventive analgesia will be presented and which have not yet been considered in the S3 guidelines.Preemptive analgesia can reduce acute postoperative pain; however, minimizing the development of chronic pain conditions can only be successful in combination with intraoperative and postoperative pain therapy as well as social and psychological support when indicated (preventive analgesia).Reduction of chronic postoperative pain is an important medical function which is also justified from socioeconomic perspectives. Future studies should combine several procedures for perioperative pain therapy in order to do justice to the multifactorial aspects of pain chronification and should also be planned over a sufficiently long observation time period.

A robust in situ CO2 and CO analysis system has been developed and deployed at eight sites in the NOAA Earth System Research Laboratory's (ESRL) Tall Tower Greenhouse Gas Observing Network. The network uses very tall (> 300 m) television and radio transmitter towers that provide a convenient platform for mid-boundary layer trace gas sampling. Each analyzer has three sample inlets for profile sampling, and a complete vertical profile is obtained every 15 min. The instrument suite at one site has been augmented with a cavity ring-down spectrometer for measuring CO2 and CH4. The long-term stability of the systems in the field is typically better than 0.1 ppm for CO2, 6 ppb for CO, and 0.5 ppb for CH4, as determined from repeated standard gas measurements. The instrumentation is fully automated and includes sensors for measuring a variety of status parameters, such as temperatures, pressures and flow rates that are inputs for automated alerts and quality control algorithms. These algorithms provide detailed and time-dependent uncertainty estimates for all of the gases and could be adapted to other species or analysis systems. The design emphasizes use of off the shelf parts and modularity to facilitate network operations and ease of maintenance. The systems report high-quality data with > 93% uptime. Recurrent problems and limitations of the current system are discussed along with general recommendations for high accuracy trace-gas monitoring. The network is a key component of the North American Carbon Program and a useful model for future research-grade operational greenhouse gas monitoring efforts.

The extraction and analysis of air from the snowpack (firn) at the South Pole provides atmospheric concentration histories of biogenic greenhouse gases since the beginning of the present century which confirm and expand on those derived from studies of air trapped in ice cores. Furthermore, calculations based on the inferred atmospheric concentrations of oxygen and carbon dioxide indicate that–in contrast to the past few years—the terrestrial biosphere was neither a source nor sink of C02 between ˜1977 and 1985.

We present the first reconstruction of the Northern Hemisphere (NH) high latitude atmospheric carbon monoxide (CO) mole fraction from Greenland firn air. Firn air samples were collected at three deep ice core sites in Greenland (NGRIP in 2001, Summit in 2006 and NEEM in 2008). CO records from the three sites agree well with each other as well as with recent atmospheric measurements, indicating that CO is well preserved in the firn at these sites. CO atmospheric history was reconstructed back to the year 1950 from the measurements using a combination of two forward models of gas transport in firn and an inverse model. The reconstructed history suggests that Arctic CO in 1950 was 140–150 nmol mol−1, which is higher than today's values. CO mole fractions rose by 10–15 nmol mol−1 from 1950 to the 1970s and peaked in the 1970s or early 1980s, followed by a ≈ 30 nmol mol−1 decline to today's levels. We compare the CO history with the atmospheric histories of methane, light hydrocarbons, molecular hydrogen, CO stable isotopes and hydroxyl radicals (OH), as well as with published CO emission inventories and results of a historical run from a chemistry-transport model. We find that the reconstructed Greenland CO history cannot be reconciled with available emission inventories unless unrealistically large changes in OH are assumed. We argue that the available CO emission inventories strongly underestimate historical NH emissions, and fail to capture the emission decline starting in the late 1970s, which was most likely due to reduced emissions from road transportation in North America and Europe.

Compacted snow (firn) preserves a continuous record of atmospheric composition up to a century back in time. Firn air transport modeling is essential for interpretation of firn gas records. Each site needs to be characterised individually through a tuning procedure, in which the effective diffusivity at each depth is adjusted to optimise the agreement between modeled and measured mixing ratios of a selected reference gas (usually CO2). We present the characterisation of the NEEM site, Northern Greenland (77.45° N 51.06° W), where an ensemble of ten reference tracers is used to constrain the diffusivity reconstruction. By analysing uncertainties in both data and the reference gas atmospheric histories, we can objectively assign weights to each of the gases used for the model tuning, and define a root mean square criterion that is minimised in the tuning. Each tracer constrains the firn profile differently through its unique atmospheric history and free air diffusivity, making our multiple-tracer characterisation method a clear improvement over the commonly used single-tracer tuning. Six firn air transport models are tuned to the NEEM site; all models successfully reproduce the data within a 1σ Gaussian distribution. The modern day Δage, i.e. the difference between gas age and ice age, is calculated to be 182 ± 8 yr. We find evidence that diffusivity does not vanish completely in the firn lock-in zone, as is commonly assumed. We further present the first intercomparison study of firn air models, where we introduce diagnostic scenarios designed to probe specific aspects of the model physics. Our results show that there are major differences in the way the models handle advective transport. Furthermore diffusive fractionation of isotopes in the firn is poorly constrained by the models, which has consequences for attempts to reconstruct the isotopic composition of trace gases back in time using firn air and ice core records.

[1] The multispecies analysis of daily air samples collected at the NOAA Boulder Atmospheric Observatory (BAO) in Weld County in northeastern Colorado since 2007 shows highly correlated alkane enhancements caused by a regionally distributed mix of sources in the Denver-Julesburg Basin. To further characterize the emissions of methane and non-methane hydrocarbons (propane, n-butane, i-pentane, n-pentane and benzene) around BAO, a pilot study involving automobile-based surveys was carried out during the summer of 2008. A mix of venting emissions (leaks) of raw natural gas and flashing emissions from condensate storage tanks can explain the alkane ratios we observe in air masses impacted by oil and gas operations in northeastern Colorado. Using the WRAP Phase III inventory of total volatile organic compound (VOC) emissions from oil and gas exploration, production and processing, together with flashing and venting emission speciation profiles provided by State agencies or the oil and gas industry, we derive a range of bottom-up speciated emissions for Weld County in 2008. We use the observed ambient molar ratios and flashing and venting emissions data to calculate top-down scenarios for the amount of natural gas leaked to the atmosphere and the associated methane and non-methane emissions. Our analysis suggests that the emissions of the species we measured are most likely underestimated in current inventories and that the uncertainties attached to these estimates can be as high as a factor of two.

[1] Airborne and ground-based measurements during the CalNex (California Research at the Nexus of Air Quality and Climate Change) field study in May/June 2010 show a weekend effect in ozone in the South Coast Air Basin (SoCAB) consistent with previous observations. The well-known and much-studied weekend ozone effect has been attributed to weekend reductions in nitrogen oxide (NOx = NO + NO2) emissions, which affect ozone levels via two processes: (1) reduced ozone loss by titration and (2) enhanced photochemical production of ozone due to an increased ratio of non-methane volatile organic compounds (VOCs) to NOx. In accord with previous assessments, the 2010 airborne and ground-based data show an average decrease in NOx of 46 ± 11% and 34 ± 4%, respectively, and an average increase in VOC/NOxratio of 48 ± 8% and 43 ± 22%, respectively, on weekends. This work extends current understanding of the weekend ozone effect in the SoCAB by identifying its major causes and quantifying their relative importance from the available CalNex data. Increased weekend production of a VOC-NOxoxidation product, peroxyacetyl nitrate, compared to a radical termination product, nitric acid, indicates a significant contribution from increased photochemical production on weekends. Weekday-to-weekend differences in the products of NOx oxidation show 45 ± 13% and 42 ± 12% more extensive photochemical processing and, when compared with odd oxygen (Ox = O3 + NO2), 51 ± 14% and 22 ± 17% greater ozone production efficiency on weekends in the airborne and ground-based data, respectively, indicating that both contribute to higher weekend ozone levels in the SoCAB.

High-energy proton microscopy provides unique capabilities in penetrating radiography including the combination of high spatial resolution and field-of-view, dynamic range of density for measurements, and reconstructing density variations to less than 1% inside volumes and in situ environments. We have recently proposed to exploit this novel proton radiography technique for image-guided stereotactic particle radiosurgery. Results of a first test for imaging biological and tissue-equivalent targets with high-energy (800 MeV) proton microscopy are presented here. Although we used a proton microscope setup at ITEP (Moscow, Russia) optimized for fast dynamic experiments in material research, we could reach a spatial resolution of 150 μm with approximately 10 10 protons per image. The potential of obtaining high-resolution online imaging of the target using a therapeutic proton beam in the GeV energy region suggests that high-energy proton microscopy may be used for image-guided proton radiosurgery.

Global measurements of atmospheric methane have revealed a sharp decrease in the growth rate in the Northern Hemisphere during 1992. The average trend for the Northern Hemisphere during 1983–1991 was (11.6±0.2) ppbv yr−1, but the increase in 1992 was only (1.8±1.6) ppbv. In the Southern Hemisphere, the average increase (1983–1991) was (11.1±0.2) ppbv yr−1, and the 1992 increase was (7.7±1.0) ppbv. Various possibilities for a change in methane sources or sinks are discussed, but the most likely explanation is a change in an anthropogenic source such as fossil fuel exploitation, which can be rapidly and easily affected by man's activities.

MEASUREMENTS of methane in modern air1–8 and in air trapped in ice cores9–12 have shown convincingly that the abundance of atmospheric methane has been rising since the Industrial Revolution. This is a matter of concern because of the important role of methane in determining the radiative balance and chemical composition of the atmosphere13. The causes of this increase have not been identified unambiguously because of uncertainties in our understanding of the global budget of atmospheric methane14 and in how it is changing with time. Here we report on measurements of atmospheric methane from an extensive global network of flask sampling sites, which reveal that, although methane continues to accumulate in the atmosphere, there has been a substantial slowing of the global accumulation rate between 1983 and 1990. If this deceleration continues steadily, global methane concentrations will reach a maximum around the year 2006. Our results hint that changes in methane emissions in the latitude band 30–90° N may be of particular significance to this trend.

[1] Measurements of atmospheric CH4 from air samples collected weekly at 46 remote surface sites show that, after a decade of near-zero growth, globally averaged atmospheric methane increased during 2007 and 2008. During 2007, CH4 increased by 8.3 ± 0.6 ppb. CH4 mole fractions averaged over polar northern latitudes and the Southern Hemisphere increased more than other zonally averaged regions. In 2008, globally averaged CH4 increased by 4.4 ± 0.6 ppb; the largest increase was in the tropics, while polar northern latitudes did not increase. Satellite and in situ CO observations suggest only a minor contribution to increased CH4 from biomass burning. The most likely drivers of the CH4 anomalies observed during 2007 and 2008 are anomalously high temperatures in the Arctic and greater than average precipitation in the tropics. Near-zero CH4 growth in the Arctic during 2008 suggests we have not yet activated strong climate feedbacks from permafrost and CH4 hydrates.

A neuropathic component to chronic ischemic pain in peripheral arterial disease (PAD) has recently been shown using quantitative sensory testing (QST) and pain questionnaires. The aim of this study was to examine correlations between QST and pain questionnaires in patients with chronic ischemic pain.A total of 10 patients with severe PAD (Fontaine stages III and IV) without diabetes mellitus answered a questionnaire and were examined with QST. The questionnaire consisted of several validated instruments which were used to examine the intensity of pain, quality of pain and neuropathic pain (VAS, SF-MPQ, S-LANSS, NPSI).The results of the QST confirmed previously published data. Several terms of the SF-MPQ showed a correlation with parameters of the QST, such as Allodynia (QST) which correlated with the term tender (SF-MPQ) (Spearman's correlation coefficient 0.911; por =0.001) and the NPSI subscore evoked pain correlated with the QST parameter wind-up ratio (0.683; p=0.042).The results suggest that there might be correlations between psychophysical tests (QST) and pain questionnaires. Subjective perceptions of pain might be represented by a certain pattern in the QST. These connections could contribute to further clarify the pathophysiologic mechanisms leading to the perception of pain.

The intention of this study was to determine the status quo of commonly used pain therapies amongst treating physicians of different specialties and to examine their view on the problem of chronic ischemic pain.A total of 281 physicians treating patients with chronic ischemic pain were surveyed. The surveyed physicians were mainly specialists in the fields of surgery, pain therapy, and internal medicine.Mainly a pharmacological therapy (metamizol/paracetamol, weak and strong opioids) was used in the treatment of chronic ischemic pain. We found differences between the specialties, for instance pain specialists used antidepressants and anticonvulsants more often than others. Therapeutic options were also evaluated differently by surgeons, pain therapists, and internal specialists: 57% of the surgeons considered the available symptomatic treatment options as sufficient whereas only 21% of the pain specialists agreed with that opinion.The differences among the specialties and the fact that the majority of physicians characterized the available symptomatic treatment options as insufficient point towards a need to review the treatment of ischemic pain in an interdisciplinary approach.

Four-year ground-level measurements of the two primary greenhouse gases (carbon dioxide (CO2) and methane (CH4)) were conducted at Dongsha Island (DSI), situated in the northern South China Sea (SCS), from March 2010 to February 2014. Their mean mixing ratios are calculated to be 396.3 ± 5.4 ppm and 1863.6 ± 50.5 ppb, with an annual growth rate of +2.19 ± 0.5 ppm yr–1 and +4.70 ± 4.4 ppb yr–1 for CO2 and CH4, respectively, over the study period. Our results suggest that the Asian continental outflow driven by the winter northeast monsoon could have brought air pollutants into the northern SCS, as denoted by significantly elevated levels of 6.5 ppm for CO2 and 59.6 ppb for CH4, which are greater than the marine boundary layer references at Cape Kumukahi (KUM) in the tropical northern Pacific in January. By contrast, the summertime CH4 at DSI is shown to be lower than that at KUM by 19.7 ppb, whereas CO2 is shown to have no differences (

[1] Sixteen mixtures of methane (CH4) in dry air were prepared using a gravimetric technique to define a CH4 standard gas scale covering the nominal range 300–2600 nmol mol−1. It is designed to be suitable for measurements of methane in air ranging from those extracted from glacial ice to contemporary background atmospheric conditions. All standards were prepared in passivated, 5.9 L high-pressure aluminum cylinders. Methane dry air mole fractions were determined by gas chromatography with flame ionization detection, where the repeatability of the measurement is typically better than 0.1% (≤1.5 nmol mol−1) for ambient CH4 levels. Once a correction was made for 5 nmol mol−1 CH4 in the diluent air, the scale was used to verify the linearity of our analytical system over the nominal range 300–2600 nmol mol−1. The gravimetrically prepared standards were analyzed against CH4 in air standards that define the Climate Monitoring and Diagnostics Laboratory (CMDL) CMDL83 CH4 in air scale, showing that CH4 mole fractions in the new scale are a factor of (1.0124 ± 0.0007) greater than those expressed in the CMDL83 scale. All CMDL measurements of atmospheric CH4 have been adjusted to this new scale, which has also been accepted as the World Meteorological Organization (WMO) CH4 standard scale; all laboratories participating in the WMO Global Atmosphere Watch program should report atmospheric CH4 measurements to the world data center on this scale.

[1] The globally-averaged atmospheric methane abundance determined from an extensive network of surface air sampling sites was constant at similar to1751 ppb from 1999 through 2002. Assuming that the methane lifetime has been constant, this implies that during this 4-year period the global methane budget has been at steady state. We also observed a significant decrease in the difference between northern and southern polar zonal annual averages of CH4 from 1991 to 1992. Using a 3-D transport model, we show that this change is consistent with a decrease in CH4 emissions of similar to10 Tg CH4 from north of 50degreesN in the early-1990s. This decrease in emissions may have accelerated the global methane budget towards steady state. Based on current knowledge of the global methane budget and how it has changed with time, it is not possible to tell if the atmospheric methane burden has peaked, or if we are only observing a persistent, but temporary pause in its increase.

[1] For the past decade NOAA/CMDL has measured tropospheric carbon monoxide from a global network of sampling sites. The resulting data set provides an internally consistent picture of CO in the lower troposphere that is used to study its distribution, trends and budget. All measurements were referenced to the so-called CMDL Reference Scale (WMO 88), which was based on two sets of primary standards produced at CMDL during the late 1980s and early 1990s. A long-term downward trend in tropospheric CO during the 1990s, overlaid with shorter periods of increase and decrease, was indicated from the air measurements. Primary standards prepared in 1999 and 2000 suggested that the scale had drifted upward over time, and that mixing ratios determined in field samples were underestimated. We have applied a time dependent correction to our CO measurements based upon four sets of primary standards. In this paper, we describe the revision of the CO scale and our atmospheric measurements. A reanalysis of tropospheric trends through 2001 was based on the revised global data set. The results support previous reports of a decline in tropospheric CO. This decrease is now found largely confined to the Northern Hemisphere, where dramatic reductions in fossil fuel emissions have reportedly occurred. In contrast, no significant trend is determined in the Southern Hemisphere between 1991 and 2001. Globally averaged CO exhibits large interannual variability, primarily reflecting year to year changes in emissions from biomass burning. Dramatic enhancements of tropospheric CO in 1997 and 1998 resulted from exceptionally widespread wildfires which provided a strong pulse of CO to the atmosphere. In years of extensive boreal biomass burning, fire emissions can perturb CO levels over regional and global scales, disturbing oxidation/reduction chemistry in the troposphere.

Measurements of carbon monoxide (CO) in air samples collected from 27 locations between 71 degrees N and 41 degrees S show that atmospheric levels of this gas have decreased worldwide over the past 2 to 5 years. During this period, CO decreased at nearly a constant rate in the high northern latitudes. In contrast, in the tropics an abrupt decrease occurred beginning at the end of 1991. In the Northern Hemisphere, CO decreased at a spatially and temporally averaged rate of 7.3 (+/-0.9) parts per billion per year (6.1 percent per year) from June 1990 to June 1993, whereas in the Southern Hemisphere, CO decreased 4.2 (+/-0.5) parts per billion per year (7.0 percent per year). This recent change is opposite a long-term trend of a 1 to 2 percent per year increase inferred from measurements made in the Northern Hemisphere during the past 30 years.

In situ methane (CH4) measurement techniques and data from the NOAA Climate Monitoring and Diagnostics Laboratory observatories at Mauna Loa, Hawaii, and Barrow, Alaska, are presented. For Mauna Loa, the data span the time period April 1987 to April 1994. At Barrow the measurements cover the period January 1986 to January 1994. Sixty air samples per day were measured with a fully automated gas chromatograph using flame ionization detection. Details of the experimental methods and procedures are given. Data are presented and assessed over various timescales. The average peak to peak seasonal cycle amplitudes obtained from four harmonics fitted to the detrended data were 25.1 ppb at Mauna Loa and 47.2 ppb at Barrow. When the seasonal cycle amplitude during each calendar year was determined as the difference between the maximum and minimum value from a smooth curve fitted to the data, the average amplitudes were (30.6±4.2) ppb at Mauna Loa and (57.5±11.4) ppb at Barrow. A discrepancy exists between these two methods due to the temporal variability in the positions of the seasonal maxima. The average trend at Mauna Loa was 9.7 ppb yr−1, but this trend was observed to decrease at a rate of 1.5 ppb yr−2. For Barrow the average trend was 8.5 ppb yr−1, and the rate of decrease in the trend was 2.1 ppb yr−2. At Mauna Loa, a diurnal cycle was sometimes observed with an amplitude of up to 10 ppb when averaged over 1 month.