Observations of HONO by laser-induced fluorescence at the South Pole during ANTCI 2003

Observations of nitrous acid (HONO) by laser-induced fluorescence (LIF) at the South Pole taken during the Antarctic Troposphere Chemistry Investigation (ANTCI), which took place over the time period of Nov. 15, 2003 to Jan. 4, 2004, are presented here. The median observed mixing ratio of HONO 10 m above the snow was 5.8 pptv (mean value 6.3 pptv) with a maximum of 18.2 pptv on Nov 30th, Dec 1st, 3rd, 15th, 17th, 21st, 22nd, 25th, 27th and 28th. The measurement uncertainty is ±35%. The LIF HONO observations are compared to concurrent HONO observations performed by mist chamber/ion chromatography (MC/IC). The HONO levels reported by MC/IC are about 7.2 ± 2.3 times higher than those reported by LIF. Citation: Liao, W., A. T. Case, J. Mastromarino, D. Tan, and J. E. Dibb (2006), Observations of HONO by laser-induced fluorescence at the South Pole during ANTCI 2003, Geophys. Res. Lett., 33, L09810, doi:10.1029/2005GL025470

Resonance fluorescence in a band gap material: Direct numerical simulation of non-Markovian evolution

A numerical method of calculating the non-Markovian evolution of a driven atom radiating into a structured continuum is developed. The formal solution for the atomic reduced density matrix is written as a Markovian algorithm by introducing a set of additional, virtual density matrices which follow, to the level of approximation of the algorithm, all the possible trajectories of the photons in the electromagnetic field. The technique is perturbative in the sense that more virtual density matrices are required as the product of the effective memory time and the effective coupling strength become larger. The number of density matrices required is given by $3^{M}$ where $M$ is the number of timesteps per memory time. The technique is applied to the problem of a driven two-level atom radiating close to a photonic band gap and the steady-state correlation function of the atom is calculated.Comment: 14 pages, 9 figure

Reactive nitrogen in Asian continental outflow over the western Pacific: Results from the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) airborne mission

We present here results for reactive nitrogen species measured aboard the NASA DC-8 aircraft during the Transport and Chemical Evolution over the Pacific (TRACE-P) mission. The large-scale distributions total reactive nitrogen (NOy,sum = NO + NO2 + HNO3 + PAN + C1–C5alkyl nitrates) and O3 and CO were better defined in the boundary layer with significant degradation of the relationships as altitude increased. Typically, NOy,sum was enhanced over background levels of ∼260 pptv by 20-to-30-fold. The ratio C2H2/CO had values of 1–4 at altitudes up to 10 km and as far eastward as 150°E, implying significant vertical mixing of air parcels followed by rapid advection across the Pacific. Analysis air parcels originating from five principal Asian source regions showed that HNO3 and PAN dominated NOy,sum. Correlations of NOy,sum with C2Cl4 (urban tracer) were not well defined in any of the source regions, and they were only slightly better with CH3Cl (biomass tracer). Air parcels over the western Pacific contained a complex mixture of emission sources that are not easily resolvable as shown by analysis of the Shanghai mega-city plume. It contained an intricate mixture of pollution emissions and exhibited the highest mixing ratios of NOy,sum species observed during TRACE-P. Comparison of tropospheric chemistry between the earlier PEM-West B mission and the recent TRACE-P data showed that in the boundary layer significant increases in the mixing ratios of NOy,sum species have occurred, but the middle and upper troposphere seems to have been affected minimally by increasing emissions on the Asian continent over the last 7 years

Improving regional ozone modeling through systematic evaluation of errors using the aircraft observations during the International Consortium for Atmospheric Research on Transport and Transformation

During the operational phase of the ICARTT field experiment in 2004, the regional air quality model STEM showed a strong positive surface bias and a negative upper troposphere bias (compared to observed DC-8 and WP-3 observations) with respect to ozone. After updating emissions from NEI 1999 to NEI 2001 (with a 2004 large point sources inventory update), and modifying boundary conditions, low-level model bias decreases from 11.21 to 1.45 ppbv for the NASA DC-8 observations and from 8.26 to −0.34 for the NOAA WP-3. Improvements in boundary conditions provided by global models decrease the upper troposphere negative ozone bias, while accounting for biomass burning emissions improved model performance for CO. The covariances of ozone bias were highly correlated to NOz, NOy, and HNO3 biases. Interpolation of bias information through kriging showed that decreasing emissions in SE United States would reduce regional ozone model bias and improve model correlation coefficients. The spatial distribution of forecast errors was analyzed using kriging, which identified distinct features, which when compared to errors in postanalysis simulations, helped document improvements. Changes in dry deposition to crops were shown to reduce substantially high bias in the forecasts in the Midwest, while updated emissions were shown to account for decreases in bias in the eastern United States. Observed and modeled ozone production efficiencies for the DC-8 were calculated and shown to be very similar (7.8) suggesting that recurring ozone bias is due to overestimation of NOx emissions. Sensitivity studies showed that ozone formation in the United States is most sensitive to NOx emissions, followed by VOCs and CO. PAN as a reservoir of NOx can contribute to a significant amount of surface ozone through thermal decomposition

Phase preparation by atom counting of Bose-Einstein condensates in mixed states

We study the build up of quantum coherence between two Bose-Einstein condensates which are initially in mixed states. We consider in detail the two cases where each condensate is initially in a thermal or a Poisson distribution of atom number. Although initially there is no relative phase between the condensates, a sequence of spatial atom detections produces an interference pattern with arbitrary but fixed relative phase. The visibility of this interference pattern is close to one for the Poisson distribution of two condensates with equal counting rates but it becomes a stochastic variable in the thermal case, where the visibility will vary from run to run around an average visibility of $\pi /4.$ In both cases, the variance of the phase distribution is inversely proportional to the number of atom detections in the regime where this number is large compared to one but small compared with the total number of atoms in the condensates.Comment: 9 pages, 6 PostScript figure, submitted to PR

The DAVID Gene Functional Classification Tool: a novel biological module-centric algorithm to functionally analyze large gene lists

The DAVID gene functional classification tool uses a novel fuzzy clustering algorithm to condense a list of genes or associated biological terms into organized classes of related genes or biology, called biological modules

Prevalence and impacts of upper limb morbidity after treatment for breast cancer: a cross-sectional study of lymphedema and function.

A cross-sectional study screened lymphedema, impaired upper limb function (ULF) and quality of life (QOL) in women post-breast cancer. Women attending review appointments who had completed surgery, chemotherapy and radiotherapy, were without recurrence, and could complete questionnaires in English were invited. Medical records were reviewed and questionnaires completed: the Morbidity Screening Tool (MST), Disability of the Arm, Shoulder and Hand questionnaire (DASH), and Functional Assessment of Cancer Therapy for breast cancer QOL questionnaire (FACTB+4). The vertical perometer (400T) measured percentage upper limb volume difference (%LVD), with 10% or greater difference diagnosed as lymphedema. Of 617 participants (mean age 62.3y, SD 10.0; mean time since treatment 63.0 months, SD 46.6), sufficient questionnaire data were available for 613 and perometry data for 417. Using the MST, 21.9% self-reported impaired ULF, 19.8% lymphedema, and 9.2% both. Based on %LVD, 26.5% had lymphedema. Histogram analysis for individuals in the first eight twelve-month intervals after treatment found impaired ULF prevalence peaked at three to five years and lymphedema at three years. Significantly worse function (DASH) and QOL (FACT B+4) resulted for those with morbidity (p<0.000). This provides evidence that impaired ULF and lymphedema negatively affect QOL years after treatment and are not necessarily linked.sch_phy1pub3633pub

Comparison of breast cancer-related lymphedema (Upper Limb Swelling) prevalence estimated using objective and subjective criteria and relationship with quality of life

This study aimed to investigate lymphedema prevalence using three different measurement/diagnostic criterion combinations and explore the relationship between lymphedema and quality of life for each, to provide evaluation of rehabilitation. Cross-sectional data from 617 women attending review appointments after completing surgery, chemotherapy, and radiotherapy included the Morbidity Screening Tool (MST; criterion: yes to lymphedema); Lymphedema and Breast Cancer Questionnaire (LBCQ; criterion: yes to heaviness and/or swelling); percentage limb volume difference (perometer: %LVD; criterion: 10%+ difference); and the Functional Assessment of Cancer Therapy breast cancer-specific quality of life tool (FACT B+4). Perometry measurements were conducted in a clinic room. Between 341 and 577 participants provided sufficient data for each analysis, with mean age varying from 60 to 62 (SD 9.95-10.03) and median months after treatment from 49 to 51. Lymphedema prevalence varied from 26.2% for perometry %LVD to 20.5% for the MST and 23.9% for the LBCQ; differences were not significant. Limits of agreement analysis between %LVD and the subjective measures showed little consistency, while moderate consistency resulted between the subjective measures. Quality of life differed significantly for women with and without lymphedema only when subjective measurements were used. Results suggest that subjective and objective tools investigate different aspects of lymphedema. 2013 Catherine Bulley et al.sch_phy2013pub3233pub80756