3,033 research outputs found

    High emission rate of sulfuric acid from Bezymianny volcano, Kamchatka

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    High concentrations of primary sulfuric acid (H2SO4) in fumarolic gases and high emission rate of sulfuric acid aerosol in the plume were measured at Bezymianny volcano, an active dome-growing andesitic volcano in central Kamchatka. Using direct sampling, filter pack sampling, and differential optical absorption spectroscopy measurements, we estimated an average emission of H2SO4 at 243 Âą 75 t/d in addition to an average SO2 emission of 212 Âą 65 t/d. The fumarolic gases of Bezymianny correspond to arc gases released by several magma bodies at different stages of degassing and contain 25-92% of entrained air. H2SO4 accounts for 6-87 mol% of the total sulfur content, 42.8 mol% on average, and SO2 is the rest. The high H2SO4 in Bezymianny fumaroles can be explained by catalytic oxidation of SO2 inside the volcanic dome. Because sulfate aerosol is impossible to measure remotely, the total sulfur content in a plume containing significant H2SO4 may be seriously underestimated

    Development of high-resolution infrared thermographic imaging method as a diagnostic tool for acute undifferentiated limp in young children

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    Acute limp is a common presenting condition in the paediatric emergency department. There are a number of causes of acute limp that include traumatic injury, infection and malignancy. These causes in young children are not easily distinguished. In this pilot study, an infrared thermographic imaging technique to diagnose acute undifferentiated limp in young children was developed. Following required ethics approval, 30 children (mean age = 5.2 years, standard deviation = 3.3 years) were recruited. The exposed lower limbs of participants were imaged using a high-resolution thermal camera. Using predefined regions of interest (ROI), any skin surface temperature difference between the healthy and affected legs was statistically analysed, with the aim of identifying limp. In all examined ROIs, the median skin surface temperature for the affected limb was higher than that of the healthy limb. The small sample size recruited for each group, however, meant that the statistical tests of significant difference need to be interpreted in this context. Thermal imaging showed potential in helping with the diagnosis of acute limp in children. Repeating a similar study with a larger sample size will be beneficial to establish reproducibility of the results

    Oral mucositis and selective elimination of oral flora in head and neck cancer patients receiving radiotherapy: a double-blind randomised clinical trial

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    Mucositis is an acute inflammation of the oral mucosa because of radiotherapy and/or chemotherapy. All patients receiving radiotherapy in the head and neck region develop oral mucositis. The aim of this study was to analyse the effects of selective oral flora elimination on radiotherapy-induced oral mucositis, in a double-blind, randomised, placebo-controlled trial. Sixty-five patients with a malignant tumour in the head and neck regions to be treated with primary curative or postoperative radiotherapy participated in this study. The patients received either the active lozenges of 1 g containing polymyxin E 2 mg, tobramycin 1.8 mg and amphotericin B 10 mg (PTA) (33 patients) or the placebo lozenges (32 patients), four times daily during the full course of radiotherapy. Mucositis, changes in the oral flora, quality of feeding and changes of total body weight were assessed. Mucositis score did not differ between the groups during the first 5 weeks of radiotherapy. Nasogastric tube feeding was needed in six patients (19%) of the placebo group and two patients (6%) of the PTA group (P=0.08). Mean weight loss after 5 weeks of radiation was less in the PTA group (1.3 kg) (s.d.: 3.0) than in the placebo group (2.8 kg) (s.d.: 2.9) (P=0.05). Colonisation index of Candida species and Gram-negative bacilli was reduced in the PTA group and not in the placebo group (P<0.05). No effect on other microorganisms was detected. In conclusion, selective oral flora elimination in head and neck irradiation patients does not prevent the development of severe mucositis. Record 8 of 10 - SilverPlatter MEDLINE(R)

    People and Things on the Move: Domestic Material Culture, Poverty and Mobility in Victorian London

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    © 2016, The Author(s). The development of what Mayne and Lawrence (Urban History 26: 325–48, 1999) termed “ethnographic” approaches to studying nineteenth-century households and urban communities has gathered momentum in recent years. As such research agendas have taken hold and been applied to new contexts, so critiques, methodological developments, and new intellectual and theoretical currents, have provided opportunities to enhance and develop approaches. This article contributes to this on-going process. Drawing upon household archaeological research on Limehouse, a poor neighborhood in Victorian London, and inspired by the theoretical insights provided by the “new mobilities paradigm,” it aims to place “mobility” as a central and enabling intellectual framework for understanding the relationships between people, place, and poverty. Poor communities in nineteenth-century cities were undeniably mobile and transient. Historians and archaeologists have often regarded this mobility as an obstacle to studying everyday life in such contexts. However, examining temporal routines and geographical movements across a variety of time frames and geographical scales, this article argues that mobility is actually key to understanding urban life and an important mechanism for interpreting the fragmented material and documentary traces left by poor households in the nineteenth-century metropolis.We are grateful to the UK’s Arts and Humanities Research Council who funded the research upon which this paper is based (Grant Reference AH/E002285/1): ‘Living in Victorian London: Towards a Material History of Everyday Domestic Life in the Nineteenth-Century Metropolis

    Evolutionary history and leaf succulence as explanations for medicinal use in aloes and the global popularity of Aloe vera

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    BACKGROUND: Aloe vera supports a substantial global trade yet its wild origins, and explanations for its popularity over 500 related Aloe species in one of the world\u27s largest succulent groups, have remained uncertain. We developed an explicit phylogenetic framework to explore links between the rich traditions of medicinal use and leaf succulence in aloes. RESULTS: The phylogenetic hypothesis clarifies the origins of Aloe vera to the Arabian Peninsula at the northernmost limits of the range for aloes. The genus Aloe originated in southern Africa ~16 million years ago and underwent two major radiations driven by different speciation processes, giving rise to the extraordinary diversity known today. Large, succulent leaves typical of medicinal aloes arose during the most recent diversification ~10 million years ago and are strongly correlated to the phylogeny and to the likelihood of a species being used for medicine. A significant, albeit weak, phylogenetic signal is evident in the medicinal uses of aloes, suggesting that the properties for which they are valued do not occur randomly across the branches of the phylogenetic tree. CONCLUSIONS: Phylogenetic investigation of plant use and leaf succulence among aloes has yielded new explanations for the extraordinary market dominance of Aloe vera. The industry preference for Aloe vera appears to be due to its proximity to important historic trade routes, and early introduction to trade and cultivation. Well-developed succulent leaf mesophyll tissue, an adaptive feature that likely contributed to the ecological success of the genus Aloe, is the main predictor for medicinal use among Aloe species, whereas evolutionary loss of succulence tends to be associated with losses of medicinal use. Phylogenetic analyses of plant use offer potential to understand patterns in the value of global plant diversity

    Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

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    A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE

    Measurement of the t t-bar production cross section in the dilepton channel in pp collisions at sqrt(s) = 7 TeV

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    The t t-bar production cross section (sigma[t t-bar]) is measured in proton-proton collisions at sqrt(s) = 7 TeV in data collected by the CMS experiment, corresponding to an integrated luminosity of 2.3 inverse femtobarns. The measurement is performed in events with two leptons (electrons or muons) in the final state, at least two jets identified as jets originating from b quarks, and the presence of an imbalance in transverse momentum. The measured value of sigma[t t-bar] for a top-quark mass of 172.5 GeV is 161.9 +/- 2.5 (stat.) +5.1/-5.0 (syst.) +/- 3.6(lumi.) pb, consistent with the prediction of the standard model.Comment: Replaced with published version. Included journal reference and DO

    Combined search for the quarks of a sequential fourth generation

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    Results are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and down type in decay channels with at least one isolated muon or electron. Limits on the mass of the fourth-generation quarks and the relevant Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a simple extension of the standard model with a sequential fourth generation of fermions. The existence of mass-degenerate fourth-generation quarks with masses below 685 GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25 GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about +/- 20 GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions.Comment: Replaced with published version. Added journal reference and DO
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