1,836 research outputs found

    Regularity Bounds on Zakharov System Evolutions

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    Spatial regularity properties of certain global-in-time solutions of the Zakharov system are established. In particular, the evolving solution u(t)u(t) is shown to satisfy an estimate \Hsup s {u(t)} \leq C {{|t|}^{(s-1)+}}, where HsH^s is the standard spatial Sobolev norm. The proof is an adaptation of earlier work on the nonlinear Schr\"odinger equation which reduces matters to bilinear estimates.Comment: 10 page

    X- and gamma-ray studies of HESS J1731-347 coincident with a newly discovered SNR

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    In the survey of the Galactic plane conducted with H.E.S.S., many VHE gamma-ray sources were discovered for which no clear counterpart at other wavelengths could be identified. HESS J1731-347 initially belonged to this source class. Recently however, the new shell-type supernova remnant (SNR) G353.6-0.7 was discovered in radio data, positionally coinciding with the VHE source. We will present new X-ray observations that cover a fraction of the VHE source, revealing nonthermal emission that most likely can be interpreted as synchrotron emission from high-energy electrons. This, along with a larger H.E.S.S. data set which comprises more than twice the observation time used in the discovery paper, allows us to test whether the VHE source may indeed be attributed to shell-type emission from that new SNR. If true, this would make HESS J1731-347 a new object in the small but growing class of non-thermal shell-type supernova remnants with VHE emission.Comment: 4 pages, 5 figures, to appear in proceedings of the 31st ICRC, Lodz, Polan

    Comparison of cancer diagnostic intervals before and after implementation of NICE guidelines: analysis of data from the UK General Practice Research Database

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    This is the final version of the article. Available from Nature Publishing Group via the DOI in this record.BACKGROUND: The primary aim was to use routine data to compare cancer diagnostic intervals before and after implementation of the 2005 NICE Referral Guidelines for Suspected Cancer. The secondary aim was to compare change in diagnostic intervals across different categories of presenting symptoms. METHODS: Using data from the General Practice Research Database, we analysed patients with one of 15 cancers diagnosed in either 2001-2002 or 2007-2008. Putative symptom lists for each cancer were classified into whether or not they qualified for urgent referral under NICE guidelines. Diagnostic interval (duration from first presented symptom to date of diagnosis in primary care records) was compared between the two cohorts. RESULTS: In total, 37,588 patients had a new diagnosis of cancer and of these 20,535 (54.6%) had a recorded symptom in the year prior to diagnosis and were included in the analysis. The overall mean diagnostic interval fell by 5.4 days (95% CI: 2.4-8.5; P<0.001) between 2001-2002 and 2007-2008. There was evidence of significant reductions for the following cancers: (mean, 95% confidence interval) kidney (20.4 days, -0.5 to 41.5; P=0.05), head and neck (21.2 days, 0.2-41.6; P=0.04), bladder (16.4 days, 6.6-26.5; P≤0.001), colorectal (9.0 days, 3.2-14.8; P=0.002), oesophageal (13.1 days, 3.0-24.1; P=0.006) and pancreatic (12.6 days, 0.2-24.6; P=0.04). Patients who presented with NICE-qualifying symptoms had shorter diagnostic intervals than those who did not (all cancers in both cohorts). For the 2007-2008 cohort, the cancers with the shortest median diagnostic intervals were breast (26 days) and testicular (44 days); the highest were myeloma (156 days) and lung (112 days). The values for the 90th centiles of the distributions remain very high for some cancers. Tests of interaction provided little evidence of differences in change in mean diagnostic intervals between those who did and did not present with symptoms specifically cited in the NICE Guideline as requiring urgent referral. CONCLUSION: We suggest that the implementation of the 2005 NICE Guidelines may have contributed to this reduction in diagnostic intervals between 2001-2002 and 2007-2008. There remains considerable scope to achieve more timely cancer diagnosis, with the ultimate aim of improving cancer outcomes.This research was funded by the National Cancer Action Team and the Department of Health Cancer Policy Team. The views contained in it are those of the authors and do not represent Department of Health policy. We can confirm that the corresponding author has had full access to the data and final responsibility for the decision to submit for publication. We would like to thank Rosemary Tate for early input into the protocol, staff of the GPRD for help in understanding the data. OCU is supported by the Peninsula Collaboration for Leadership in Applied Health Research and Care. Ethical approval: Independent Scientific Advisory Committee, numbers 09_0110 and 09_0111

    Relative space-time asymmetries in pion and nucleon production in non-central nucleus-nucleus collisions at high energies

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    We propose to use the ratio of the pion-proton correlation functions evaluated under different conditions to study the relative space-time asymmetries in pion and proton emission (pion and nucleon source relative shifts) in high energy heavy ion collision. We address the question of the non-central collisions, where the sources can be shifted spatially both in the longitudinal and in the transverse directions in the reaction plane. We use the RQMD event generator to illustrate the effect and the technique.Comment: RevTex, 4 pages, 3 figures included as eps file

    Pion interferometry with pion-source-medium interactions

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    An extended pion source, which can be temporarily created by a high energy nuclear collision, will also absorb and distort the outgoing pions. We discuss how this effect alters the interferometric pattern of the two-pion momentum correlation function. In particular, we show that the two-pion correlation function decreases rapidly when the opening angle between the pions increases. The opening-angle dependence should serve as a new means of obtaining information about the pion source in the analysis of experimental data.Comment: 14 pages (revtex) and 9 figures (uuencoded), Caltech preprint MAP-175, Indiana Univ. preprint IU/NTC 914-1

    Antiglycation and Antioxidant Activities and HPTLC Analysis of Boswellia sacra Oleogum Resin: The Sacred Frankincense

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    Purpose: To evaluate antiglycation and antioxidant activities as undertake HPTLC analysis of Boswellia sacra resin.Methods: Sub-fractionation of the crude methanol extract of Hougari regular (HR) grade resin of Boswellia sacra was carried out by vacuum liquid chromatography. Free radical scavenging and antiglycation activities of sub-fractions were characterized in order to assess their anti-aging properties. Furthermore, high performance thin layer chromatography (HPTLC) analysis of Boswellia sacra resins was also carried out.Results: Polar fractions of the extract obtained exhibited the highest antiglycation activity while nonpolar fractions showed more than 50 % inhibition in superoxide anion scavenging assay. Scavenging activity of reactive oxygen species results indicate that non-polar sub-fractions showed &gt; 50 % inhibition, except Shabi frankincense (SF) oil which showed 33 % inhibition. Dichloromethane (CH2Cl2) fraction, 40 % dichloromethane (CH2Cl2)/n-hexane sub-fraction, and SF oil showed moderate activity in di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) assay. Furthermore, HPTLC analysis indicates the presence of 11-keto-β-boswellic acid (KBA) and 3-O-acetyl-11-keto-β-boswellic acid (AKBA) along with some other terpenoids.Conclusion: Various sub-fractions of Boswellia sacra exert effective antiglycation and antioxidant activities. The extracts should be studied further for possible formulation into pharmaceutical products.Keywords: Frankincense, Boswellia sacra, Terpenoids, HPTLC, Antioxidant, Antiglycatio

    Efficacy of Avicennia marina (Forsk.) Vierh. leaves extracts against some atmospheric fungi

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    Crude ethanolic extract of Avicennia marina leaves was tested against seven allergenic fungi viz., Alternaria alternata, Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Cladosporium herbarum, Penicillium notatum and Saccharomyces cerevisiae using five different solvents: dimethyl sulphoxide (DMSO), distilled water (DW), chloroform, ethanol and acetone at 2000, 4000 and 6000 ppm doses. Dose dependent tendency in the increase or decrease in the growth of fungi was observed. Two synthetic drugs miconazole and amphotericin-B were used as positive control. Miconazole was 100% effective against A. alternata, C. herbatum, P. notatum and S. cerevisiae with the concentrations of 95.00 ± 1.62, 78.00 ± 4.99, 100.00 ± 0.69 and 110.00 ± 2.33 (μg/ml of SDA medium), respectively. Amphotericin-B completely controlled the growth of A. flavus, A. fumigatus and A. niger in the concentration of 24.00 ± 17.00, 30.00 ± 15.66 and 18.00 ± 18.34 (μg/ml of SDA medium), respectively. Distilled water and DMSO were considered to be the most effective solvents preventing 83.00 ± 4.73% growth of A. niger, 80.33 ± 5.60% A. flavus, 78.58 ± 3.18% A. alternata, 72.91 ± 7.96% P. notatum, 65.25 ± 3.55% C. herbarum, 63.25 ± 4.52% A. fumigatus and 48.5 ± 7.89% S. cerevisiae. Statistically, the results were compared with negative control and found to be highly significant (p&lt;0.01).Key words: Allergenic fungi, inhibition, dose dependent, growth control, synthetic drugs
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