184 research outputs found

    Saturated laser fluorescence in turbulent sooting flames at high pressure

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    The primary objective was to develop a quantitative, single pulse, laser-saturated fluorescence (LSF) technique for measurement of radical species concentrations in practical flames. The species of immediate interest was the hydroxyl radical. Measurements were made in both turbulent premixed diffusion flames at pressures between 1 and 20 atm. Interferences from Mie scattering were assessed by doping with particles or by controlling soot loading through variation of equivalence ratio and fuel type. The efficacy of the LSF method at high pressure was addressed by comparing fluorescence and adsorption measurements in a premixed, laminar flat flame at 1-20 atm. Signal-averaging over many laser shots is sufficient to determine the local concentration of radical species in laminar flames. However, for turbulent flames, single pulse measurements are more appropriate since a statistically significant number of laser pulses is needed to determine the probability function (PDF). PDFs can be analyzed to give true average properties and true local kinetics in turbulent, chemically reactive flows

    PSS5 RESTORÂź VERSUS ACRILISAÂź : ND-YAG LASER INCIDENCE RATE COMPARISON 18 MONTHS AFTER SURGERY

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    Digitalitzat per Artypla

    Prise en charge et coûts de la bronchopneumopathie chronique obstructive en France en 2011

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    RĂ©sumĂ©IntroductionCette Ă©tude vise Ă  estimer une prĂ©valence de la bronchopneumopathie chronique obstructive (BPCO) traitĂ©e et les coĂ»ts associĂ©s par degrĂ© de sĂ©vĂ©ritĂ©.MĂ©thodeElle a Ă©tĂ© conduite sur les donnĂ©es 2011 de l’échantillon gĂ©nĂ©raliste de bĂ©nĂ©ficiaires (EGB). Cet Ă©chantillon reprĂ©sente 1/97e des bĂ©nĂ©ficiaires des principaux rĂ©gimes d’assurance maladie obligatoire. Les cas et leur sĂ©vĂ©ritĂ© ont Ă©tĂ© identifiĂ©s Ă  partir d’algorithmes originaux. Les coĂ»ts ont Ă©tĂ© Ă©tablis dans une perspective collective.RĂ©sultatsLe taux de prĂ©valence minimale de la BPCO traitĂ©e a Ă©tĂ© estimĂ© Ă  3,8 % dans la population ĂągĂ©e de 40ans et plus, et 1,9 % tous Ăąges confondus. La population (58,2 % d’hommes) avait 68,8±12,7ans d’ñge moyen. Au total, 6,2 % des patients ont eu des consommations de soins Ă©vocatrices d’un stade trĂšs sĂ©vĂšre, 8,1 %, 13,8 % et 71,9 % d’un stade sĂ©vĂšre, modĂ©rĂ© ou peu sĂ©vĂšre. Sur une annĂ©e, 28,8 % ont consultĂ© un pneumologue, 5,0 % ont Ă©tĂ© hospitalisĂ©s (≄24h) pour BPCO et 6,7 % sont dĂ©cĂ©dĂ©s. En moyenne, les patients ont eu 1,7±1,5 exacerbations/an et seulement 61,4 % ont reçu un traitement mĂ©dicamenteux spĂ©cifique. La consommation annuelle moyenne de soins d’un patient a Ă©tĂ© estimĂ©e Ă  9382€ dont 5516€ attribuable Ă  la BPCO.ConclusionCette Ă©tude utilisant des bases de donnĂ©es mĂ©dico-administratives confirme l’importance du fardeau Ă©pidĂ©miologique et Ă©conomique de la BPCO en France.SummaryObjectivesTo estimate the prevalence of treated chronic obstructive pulmonary disease (COPD) and its associated costs by stage of severity.MethodsThe study was conducted on the 2011 data of the french general beneficiary sample database (EGB). EGB is a 1/97th sample of the whole population of the beneficiaries of the main compulsory national health insurances. COPD cases and the level of severity of the disease have been identified using new algorithms established from the available parameters in EGB. Costs were estimated using a collective perspective.ResultsThe minimal prevalence of treated COPD was estimated at 3.8% in patients of 40 years and older and 1.9% regardless of the age of individuals. This population was predominantly male (58.2%) with a mean age of 68.8 years (±12.7). A total of 6.2% of patients had a health-care utilization suggestive of a very severe stage of COPD and 8.1%, 13.8% and 71.9% suggestive of severe, moderate and mild stages respectively. Over one year, 28.8% of patients visited a specialist respiratory physician, 5.0% were hospitalized (≄24h) for COPD and 6.7% died. Patients experienced an average of 1.7 (±1.5) exacerbations per year and only 61.4% received specific pharmacological treatment for COPD during the year. The average yearly health-care cost of a patient with COPD was estimated at €9382, with €5342 directly related to COPD.ConclusionThis study based on medico-administrative databases confirms the high epidemiological and economic burden of COPD in France

    Elucidating the Influence of the Activation Energy on Reaction Rates by Simulations Based on a Simple Particle Model

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    An application for visualizing the dynamic properties of an equimolar binary mixture of isotropic reactive particles is presented. By introducing a user selectable choice for the activation energy, the application is useful to demonstrate qualitatively that the reaction rate depends on the above choice and on temperature. The application is based on a 2D realistic dynamic model where atoms move because of their thermal energies and the trajectories are determined by solving numerically Newton’s laws according to a Molecular Dynamics (MD) scheme. Collisions are monitored as time progresses, and every time the collision energy is larger than the selected activation energy, a reactive event occurs. By examining the time evolution of the configurations, it is possible to observe that the number of reactive collisions is always smaller than the total number of collisions. However, the number of reactive events increases on raising the temperature and/or by decreasing the activation energy. The above observations, as well as more quantitative analyses of the simulation data, are useful in elucidating the connections existing among particle kinetic energy, temperature, and activation energy of the reaction. The application can be used at different levels of detail and in different instruction levels. Qualitative visual observations of the progress of the reaction are suitable at all levels of instruction. Systematic investigations on the effect of changes of temperature and activation energy, suitable for senior high school and college courses and useful to gain insight into kinetic models and Arrhenius’ law, are also reported

    Selection of suitable reference genes for quantitative real-time polymerase chain reaction in human meningiomas and arachnoidea

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    <p>Abstract</p> <p>Findings</p> <p>At first 32 housekeeping genes were analyzed in six randomly chosen meningiomas, brain and dura mater using geNorm, NormFinder, Bestkeeper-1 software and the comparative ΔCt method. Reference genes were ranked according to an integration tool for analyzing reference genes expression based on those four algorithms. Eight highest ranked reference genes (CASC3, EIF2B1, IPO8, MRPL19, PGK1, POP4, PPIA, and RPL37A) plus GAPDH and ACTB were then analyzed in 35 meningiomas, arachnoidea, dura mater and normal brain. NormFinder and Bestkeeper-1 identified RPL37A as the most stable expressed gene in meningiomas and their normal control tissue. NormFinder also determined the best combination of genes: RPL37A and EIF2B1. Commonly used reference genes GAPDH and ACTB were considered least stable genes. The critical influence of reference genes on qPCR data analysis is shown for VEGFA transcription patterns.</p> <p>Background</p> <p>In meningiomas quantitative real-time reverse transcription-polymerase chain reaction (qPCR) is most frequently used for accurate determination of gene expression using various reference genes. Although meningiomas are a heterogeneous group of tissue, no data have been reported to validate reference genes for meningiomas and their control tissues.</p> <p>Conclusions</p> <p>RPL37A is the optimal single reference gene for normalization of gene expression in meningiomas and their control tissues, although the use of the combination of RPL37A and EIF2B1 would provide more stable results.</p

    Understanding Action and Adventure Sports Participation-An Ecological Dynamics Perspective.

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    Previous research has considered action and adventure sports using a variety of associated terms and definitions which has led to confusing discourse and contradictory research findings. Traditional narratives have typically considered participation exclusively as the pastime of young people with abnormal characteristics or personalities having unhealthy and pathological tendencies to take risks because of the need for thrill, excitement or an adrenaline 'rush'. Conversely, recent research has linked even the most extreme forms of action and adventure sports to positive physical and psychological health and well-being outcomes. Here, we argue that traditional frameworks have led to definitions, which, as currently used by researchers, ignore key elements constituting the essential merit of these sports. In this paper, we suggest that this lack of conceptual clarity in understanding cognitions, perception and action in action and adventure sports requires a comprehensive explanatory framework, ecological dynamics which considers person-environment interactions from a multidisciplinary perspective. Action and adventure sports can be fundamentally conceptualized as activities which flourish through creative exploration of novel movement experiences, continuously expanding and evolving beyond predetermined environmental, physical, psychological or sociocultural boundaries. The outcome is the emergence of a rich variety of participation styles and philosophical differences within and across activities. The purpose of this paper is twofold: (a) to point out some limitations of existing research on action and adventure sports; (b) based on key ideas from emerging research and an ecological dynamics approach, to propose a holistic multidisciplinary model for defining and understanding action and adventure sports that may better guide future research and practical implications

    ‘It used to be brutal, now it’s an art’:changing negotiations of violence and masculinity in British karate

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    In most western (and indeed eastern) cultures, fighting is seen as an ultimate symbol of masculinity – an embodied display of dominance, control and violence (Bourdieu, 2001). As a space legitimising and praising performances of mimetic violence (Dunning, 1999), combat sports provide an arena where the virtues of dominance and power at the heart of conceptions of orthodox masculinity (Anderson, 2010 ) or hegemonic masculinity (Connell, 2005) can be symbolically presented by men through bodily displays of strength, physical aggression, and the taking and overcoming of pain (Bourdieu, 2001; Messner, 1990; Wacquant, 2004). Yet, over the last twenty years the focus of karate in Britain has been perceived to shift from aggressive acts of 'hitting hard' to developing and displaying controlled, acrobatic and technically precise movements. Drawn from a nine-month ethnography and 7 semi-structured interviews, this chapter explores how British male karate practitioners re/negotiate ideas of masculinity and embodiments of a masculine identity in the context of karate’s changing emphasis on, and practices of, 'violence'. This paper suggests that a 'civilising' shift (Elias and Dunning, 1986) in the competition rules increases in women’s participation in karate with men, and subsequent negotiations of mimetic violence, complicate the use of violence as a symbol of praised masculine identity within British karate . A praised masculine identity is crafted by carefully blending traits conventional deemed feminine such as technical precision, elegance and agility alongside displays of strength and dominance. Such performances challenge conceptions of an orthodox sporting masculinity and notions of hierarchical gender distinction

    Derivation of consistent hard rock (1000<Vs<3000 m/s) GMPEs from surface and down-hole recordings: Analysis of KiK-net data

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    A key component in seismic hazard assessment is the estimation of ground motion for hard rock sites, either for applications to installations built on this site category, or as an input motion for site response computation. Empirical ground motion prediction equations (GMPEs) are the traditional basis for estimating ground motion while VS30 is the basis to account for site conditions. As current GMPEs are poorly constrained for VS30 larger than 1000 m/s, the presently used approach for estimating hazard on hard rock sites consists of “host-to-target” adjustment techniques based on VS30 and Îș0 values. The present study investigates alternative methods on the basis of a KiK-net dataset corresponding to stiff and rocky sites with 500 < VS30 < 1350 m/s. The existence of sensor pairs (one at the surface and one in depth) and the availability of P- and S-wave velocity profiles allow deriving two “virtual” datasets associated to outcropping hard rock sites with VS in the range [1000, 3000] m/s with two independent corrections: 1/down-hole recordings modified from within motion to outcropping motion with a depth correction factor, 2/surface recordings deconvolved from their specific site response derived through 1D simulation. GMPEs with simple functional forms are then developed, including a VS30 site term. They lead to consistent and robust hard-rock motion estimates, which prove to be significantly lower than host-to-target adjustment predictions. The difference can reach a factor up to 3–4 beyond 5 Hz for very hard-rock, but decreases for decreasing frequency until vanishing below 2 Hz
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