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Measurements of reactive nitrogen produced by tropical thunderstorms during BIBLE-C
The Biomass Burning and Lightning Experiment phase C (BIBLE-C) aircraft mission was carried out near Darwin, Australia (12°S, 131°E) in December 2000. This was the first aircraft experiment designed to estimate lightning NO production rates in the tropics, where production is considered to be most intense. During the two flights (flights 10 and 13 made on December 9 and 11-12, respectively) enhancements of NOx (NO + NO2) up to 1000 and 1600 parts per trillion by volume (pptv, 10-s data) were observed at altitudes between 11.5 and 14 km. The Geostationary Meteorological Satellite (GMS) cloud (brightness temperature) data and ground-based lightning measurements by the Global Positioning and Tracking System (GPATS) indicate that there were intensive lightning events over the coast of the Gulf of Carpentaria, which took place upstream from our measurement area 10 to 14 h prior to the measurements. For these two flights, air in which NOx exceeded 100 pptv extended over 620 × 140 and 400 × 170 km2 (wind direction x perpendicular direction), respectively, suggesting a significant impact of lightning NO production on NOx levels in the tropics. We estimate the amount of NOx observed between 11.5 and 14 km produced by the thunderstorms to be 3.3 and 1.8 × 1025 NO molecules for flights 10 and 13, respectively. By using the GPATS lightning flash count data, column NO production rates are estimated to be 1.9-4.4 and 21-49 × 1025 NO molecules per single flash for these two flight data sets. In these estimations, it is assumed that the column NO production between 0 and 16 km is greater than the observed values between 11.5 and 14 km by a factor of 3.2, which is derived using results reported by Pickering et al. (1998). There are however large uncertainties in the GPATS lightning data in this study and care must be made when the production rates are referred. Uncertainties in these estimates are discussed. The impact on the ozone production rate is also described. Copyright 2007 by the American Geophysical Union
Autoinjection of electrons into a wake field using a capillary with attached cone
Copyright 2009 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Physics of Plasmas, 16(12), 123103, 2009 and may be found at http://dx.doi.org/10.1063/1.327115
Spectrum modulation of relativistic electrons by laser wakefield
Copyright 2008 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Applied Physics Letters, 93(8), 081501, 2008 and may be found at http://dx.doi.org/10.1063/1.297123
Rapid, progressive neuropathic arthropathy of the hip in a patient co-infected with human immunodeficiency virus, hepatitis C virus and tertiary syphilis: case report
BACKGROUND: Syphilis is a chronic infection that is classified into
three stages. In its tertiary stage, syphilis spreads to the brain, heart and
other organs; the lesions may involve the skin, mucous membranes and bones.
Neuropathic arthropathy associated with tertiary syphilis has rarely been
described in Europe and its association with HIV-HCV co-infection has not been
reported so far.This article reports the case of a man with tertiary syphilis
presenting with rapidly evolving neuropathic arthropathy of the hip and extensive
bone destruction.
CASE PRESENTATION: On initial presentation, the patient complained of
progressively worsening left-sided coxalgia without localized or generalized
inflammation. The patient reported to have no history of previous infections,
trauma or cancer. Plain x-ray films of the left coxofemoral joint showed marked
degeneration with necrosis of the proximal epiphysis of femur and morphological
alterations of the acetabulum without protrusion. Primary coxarthrosis was
diagnosed and hip arthroplasty was offered, but the patient declined treatment.
Three months later, the patient presented a marked deterioration of his general
condition. He disclosed that he was seropositive for HCV and HIV, as confirmed by
serology. Syphilis serology testing was also positive. A Girdlestone's procedure
was performed and samples were collected for routine cultures for bacteria and
acid fast bacilli, all resulting negative.Although histological findings were
inconclusive, confirmed positive serology for syphilis associated with
progressive arthropathy was strongly suggestive of tertiary syphilis, probably
exacerbated by HIV-HCV co-infection. The patient partially recovered the ability
to walk.
CONCLUSIONS: Due to the resurgence of syphilis, this disease should be considered
as a possible cause of neuropathic arthropathy when other infectious causes have
been ruled out, particularly in patients with HIV and/or HCV co-infection
Chemical Characterization of a Volatile Dubnium Compound, DbOCl3
The formation and the chemical characterization of single atoms of dubnium (Db, element 105), in the form of its volatile oxychloride, was investigated using the on-line gas phase chromatography technique, in the temperature range 350–600 °C. Under the exactly same chemical conditions, comparative studies with the lighter homologues of Group 5 in the Periodic Table clearly indicate the volatility sequence being NbOCl3 > TaOCl3 ≥ DbOCl3. From the obtained experimental results, thermochemical data for DbOCl3 were derived. The present study delivers reliable experimental information for theoretical calculations on chemical properties of transactinides
Methods and rationale of the DISCOVER CKD global observational study
Background: Real-world data for patients with chronic kidney disease (CKD), specifically pertaining to clinical management, metabolic control, treatment patterns, quality of life (QoL) and dietary patterns, are limited. Understanding these gaps using real-world, routine care data will improve our understanding of the challenges and consequences faced by patients with CKD, and will facilitate the long-term goal of improving their management and prognosis. Methods: DISCOVER CKD follows an enriched hybrid study design, with both retrospective and prospective patient cohorts, integrating primary and secondary data from patients with CKD from China, Italy, Japan, Sweden, the UK and the USA. Data will be prospectively captured over a 3-year period from >1000 patients with CKD who will be followed up for at least 1 year via electronic case report form entry during routine clinical visits and also via a mobile/tablet-based application, enabling the capture of patient-reported outcomes (PROs). In-depth interviews will be conducted in a subset of ∼100 patients. Separately, secondary data will be retrospectively captured from >2 000 000 patients with CKD, extracted from existing datasets and registries. Results: The DISCOVER CKD program captures and will report on patient demographics, biomarker and laboratory measurements, medical histories, clinical outcomes, healthcare resource utilization, medications, dietary patterns, physical activity and PROs (including QoL and qualitative interviews). Conclusions: The DISCOVER CKD program will provide contemporary real-world insight to inform clinical practice and improve our understanding of the epidemiology and clinical and economic burden of CKD, as well as determinants of clinical outcomes and PROs from a range of geographical regions in a real-world CKD setting
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