Investigation of laser induced phosphorescence and fluorescence of acetone at low pressure for molecular tagging velocimetry in gas microflows

This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.Laser-induced fluorescence and phosphorescence properties of gaseous acetone in argon are measured and analyzed in a pressure ranging from 10(5) to 10(2) Pa, with the aim of analyzing by molecular tagging velocimetry gas microflows in rarefied regimes which requires operation at low pressure. Acetone is excited at a wavelength of 266 nm and immediately emits short lifetime fluorescence rapidly followed by long lifetime phosphorescence. At atmospheric pressure, the early phosphorescence intensity is more than 600 times lower than the fluorescence one. The phosphorescence signal is rapidly decreasing with time, closely following a power law. Both fluorescence and phosphorescence signals are decreasing with pressure. The systematic analysis of fluorescence and phosphorescence of acetone molecules shows that although the signal is dramatically reduced at low pressure, the on-chip integration technique and the optimization of the acquisition parameters provide an exploitable signal for molecular tagging velocimetry in rarefied microflows, in a Knudsen number range corresponding to the early slip flow regime

The burden of breast, cervical, and colon and rectum cancer in the Balkan countries, 1990–2019 and forecast to 2030.

Background Despite effective prevention and control strategies, in countries of the Balkan region, cancers are the second leading cause of mortality, closely following circulatory system diseases. Objective To describe trends in the burden of breast, cervical, and colon and rectum cancer in the Balkan region and per country between 1990 and 2019, including a forecast to 2030. Methods We described the 2019 Global Burden of Disease (GBD) estimates for breast, cervical, and colon and rectum cancers in eleven Balkan countries over the period 1990–2019, including incidence, years lived with disability (YLD), years of life lost (YLL), and disability-adjusted life years (DALYs) rates per 100,000 population and accompanied 95% uncertainty interval. With the Autoregressive Integrated Moving Average, we forecasted these rates per country up to 2030. Results In the Balkan region, the highest incidence and DALYs rates in the study period were for colon and rectum, and breast cancers. Over the study period, the DALYs rates for breast cancer per 100,000 population were the highest in Serbia (reaching 670.84 in 2019) but the lowest in Albania (reaching 271.24 in 2019). In 2019, the highest incidence of breast cancer (85 /100,000) and highest YLD rate (64 /100,000) were observed in Greece. Romania had the highest incidence rates, YLD rates, DALY rates, and YLL rates of cervical cancer, with respective 20.59%, 23.39% 4.00%, and 3.47% increases for the 1990/2019 period, and the highest forecasted burden for cervical cancer in 2030. The highest incidence rates, YLD rates and DALY rates of colon and rectum cancers were continuously recorded in Croatia (an increase of 130.75%, 48.23%, and 63.28%, respectively), while the highest YLL rates were in Bulgaria (an increase of 63.85%). The YLL rates due to colon and rectum cancers are forecasted to progress by 2030 in all Balkan countries. Conclusion As most of the DALYs burden for breast, cervical, and colon and rectum cancer is due to premature mortality, the numerous country-specific barriers to cancer early detection and quality and care continuum should be a public priority of multi-stakeholder collaboration in the Balkan region

Methodological considerations in injury burden of disease studies across Europe: a systematic literature review

Background Calculating the disease burden due to injury is complex, as it requires many methodological choices. Until now, an overview of the methodological design choices that have been made in burden of disease (BoD) studies in injury populations is not available. The aim of this systematic literature review was to identify existing injury BoD studies undertaken across Europe and to comprehensively review the methodological design choices and assumption parameters that have been made to calculate years of life lost (YLL) and years lived with disability (YLD) in these studies. Methods We searched EMBASE, MEDLINE, Cochrane Central, Google Scholar, and Web of Science, and the grey literature supplemented by handsearching, for BoD studies. We included injury BoD studies that quantified the BoD expressed in YLL, YLD, and disability-adjusted life years (DALY) in countries within the European Region between early-1990 and mid-2021. Results We retrieved 2,914 results of which 48 performed an injury-specific BoD assessment. Single-country independent and Global Burden of Disease (GBD)-linked injury BoD studies were performed in 11 European countries. Approximately 79% of injury BoD studies reported the BoD by external cause-of-injury. Most independent studies used the incidence-based approach to calculate YLDs. About half of the injury disease burden studies applied disability weights (DWs) developed by the GBD study. Almost all independent injury studies have determined YLL using national life tables. Conclusions Considerable methodological variation across independent injury BoD assessments was observed; differences were mainly apparent in the design choices and assumption parameters towards injury YLD calculations, implementation of DWs, and the choice of life table for YLL calculations. Development and use of guidelines for performing and reporting of injury BoD studies is crucial to enhance transparency and comparability of injury BoD estimates across Europe and beyond

Burden of non-communicable disease studies in Europe: a systematic review of data sources and methodological choices

Background: Assessment of disability-adjusted life years (DALYs) resulting from non-communicable diseases (NCDs) requires specific calculation methods and input data. The aims of this study were to (i) identify existing NCD burden of disease (BoD) activities in Europe; (ii) collate information on data sources for mortality and morbidity; and (iii) provide an overview of NCD-specific methods for calculating NCD DALYs. Methods: NCD BoD studies were systematically searched in international electronic literature databases and in grey literature. We included all BoD studies that used the DALY metric to quantify the health impact of one or more NCDs in countries belonging to the European Region. Results: A total of 163 BoD studies were retained: 96 (59%) were single-country or sub-national studies and 67 (41%) considered more than one country. Of the single-country studies, 29 (30%) consisted of secondary analyses using existing Global Burden of Disease (GBD) results. Mortality data were mainly derived (49%) from vital statistics. Morbidity data were frequently (40%) drawn from routine administrative and survey datasets, including disease registries and hospital discharge databases. The majority (60%) of national BoD studies reported mortality corrections. Multimorbidity adjustments were performed in 18% of national BoD studies. Conclusion: The number of national NCD BoD assessments across Europe increased over time, driven by an increase in BoD studies that consisted of secondary data analysis of GBD study findings. Ambiguity in reporting the use of NCD-specific BoD methods underlines the need for reporting guidelines of BoD studies to enhance the transparency of NCD BoD estimates across Europe

Gasmems network: example of collaboration and exchanges opportunities

International audienceno abstrac

Molecular tagging velocimetry for gaseous microflows

International audienceThe slip flow regime is very frequently encountered in fluidic microsystems working with gases. A significant research effort has been made by a number of groups for developing accurate models of flows in this regime. A series of different boundary conditions have been proposed in the literature; they require a careful comparison with experimental data for leading to a valuable discussion about their accuracy and their range of applicability. Unfortunately, the only available experimental data concern mass or volume flow rates, whereas the direct measurement of the velocity profile is necessary for separately analyzing the role of the boundary condition and the role of the accommodation coefficient. In this paper, we propose to develop a micro molecular tagging velocimetry (µMTV) setup for measuring the velocity profile in a rectangular microchannel in the slip flow and early transition regimes. The principle of the technique is presented and the technical choice of components for the setup is detailed. The main objective is to directly access the slip velocity at the wall

Molecular tagging velocimetry for gaseous microflows

International audienceThe slip flow regime is very frequently encountered in fluidic microsystems working with gases. A significant research effort has been made by a number of groups for developing accurate models of flows in this regime. A series of different boundary conditions have been proposed in the literature; they require a careful comparison with experimental data for leading to a valuable discussion about their accuracy and their range of applicability. Unfortunately, the only available experimental data concern mass or volume flow rates, whereas the direct measurement of the velocity profile is necessary for separately analyzing the role of the boundary condition and the role of the accommodation coefficient. In this paper, we propose to develop a micro molecular tagging velocimetry (µMTV) setup for measuring the velocity profile in a rectangular microchannel in the slip flow and early transition regimes. The principle of the technique is presented and the technical choice of components for the setup is detailed. The main objective is to directly access the slip velocity at the wall

Temperature influence on the hydrodynamics of gas flows in microchannels in the slip flow regime

International audienceThe influence of temperature on isothermal rarefied gas flows in rectangular microchannels is experimentally investigated. A specific setup with accurate temperature regulation, by means of Peltier modules, has been designed, and the mass flowrate through long microchannels is measured using the constant volume method. The channels are etched by DRIE in silicon wafers and anodically bonded by Pyrex plates; their hydraulic diameter is of the order of one micrometer. The effect of temperature on flowrate is investigated in the range 287 to 317 K, for flows of helium. The flow is in the slip flow regime, with average Knudsen numbers of the order of 0.1. The experimental data are in very good agreement with a second-order slip flow model, with an accommodation coefficient close to unity, whatever the operating temperature

Gasmems network: example of collaboration and exchanges opportunities

International audienceno abstrac