99 research outputs found
Study of the unknown HONO daytime source at a European suburban site during the MEGAPOLI summer and winter field campaigns
International audienceNitrous acid measurements were carried out during the MEGAPOLI summer and winter field campaigns at SIRTA observatory in Paris surroundings. Highly variable HONO levels were observed during the campaigns, ranging from 10 ppt to 500 ppt in summer and from 10 ppt to 1.7 ppb in winter. Significant HONO mixing ratios have also been measured during daytime hours, comprised between some tenth of ppt and 200 ppt for the summer campaign and between few ppt and 1 ppb for the winter campaign. Ancillary measurements, such as NOx , O3 , photolysis frequencies, meteorological parameters (pressure, temperature, relative humidity , wind speed and wind direction), black carbon concentration , total aerosol surface area, boundary layer height and soil moisture, were conducted during both campaigns. In addition, for the summer period, OH radical measurements were made with a CIMS (Chemical Ionisation Mass Spectrometer). This large dataset has been used to investigate the HONO budget in a suburban environment. To do so, calculations of HONO concentrations using PhotoStationary State (PSS) approach have been performed, for daytime hours. The comparison of these calculations with measured HONO concentrations revealed an underestimation of the calculations making evident a missing source term for both campaigns. This unknown HONO source exhibits a bell-shaped like average diurnal profile with a maximum around noon of approximately 0.7 ppb h−1 and 0.25 ppb h−1 , during summer and winter respectively. This source is the main HONO source during daytime hours for both campaigns. In both cases, this source shows a slight positive correlation with J (NO2) and the product between J (NO2) and soil moisture. This original approach had, thus, indicated that this missing source is photolytic and might be heterogeneous occurring at ground surface and involving water content available on the ground. Published by Copernicus Publications on behalf of the European Geosciences Union. 2806 V. Michoud et al.: Study of the unknown HONO daytime sourc
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MEGAPOLI: concept of multi-scale modelling of megacity impact on air quality and climate
The EU FP7 Project MEGAPOLI: "Megacities: Emissions, urban, regional and Global Atmospheric POLlution and climate effects, and Integrated tools for assessment and mitigation" (http://megapoli.info) brings together leading European research groups, state-of-the-art scientific tools and key players from non-European countries to investigate the interactions among megacities, air quality and climate. MEGAPOLI bridges the spatial and temporal scales that connect local emissions, air quality and weather with global atmospheric chemistry and climate. The suggested concept of multi-scale integrated modelling of megacity impact on air quality and climate and vice versa is discussed in the paper. It requires considering different spatial and temporal dimensions: time scales from seconds and hours (to understand the interaction mechanisms) up to years and decades (to consider the climate effects); spatial resolutions: with model down- and up-scaling from street- to global-scale; and two-way interactions between meteorological and chemical processes
Species-specified VOC emissions derived from a gridded study in the Pearl River Delta, China
This study provides a top-down approach to establish an emission inventory of volatile organic compounds (VOC) based on ambient measurements, by combining the box model and positive matrix factorization (PMF) model. Species-specified VOC emissions, source contributions, and spatial distributions are determined based on regional-scale gridded measurements between September 2008 to December 2009 in the Pearl River Delta (PRD), China. The most prevalent anthropogenic species in the PRD was toluene estimated by the box model to be annual emissions of 167.8 ± 100.5 Gg, followed by m,p-xylene (68.0 ± 45.0 Gg), i-pentane (49.2 ± 40.0 Gg), ethene (47.6 ± 27.6 Gg), n-butane (47.5 ± 40.7 Gg), and benzene (46.8 ± 29.0 Gg). Alkanes such as propane, i-butane, and n-pentane were 2–8 times higher in box model than emission inventories (EI). Species with fewer emissions were highly variable between EI and box model results. Hotspots of VOC emissions were identified in southwestern PRD and port areas, which were not reflected by bottom-up EI. This suggests more research is needed for VOC emissions in the EI, especially for fuel evaporation, industrial operations and marine vessels. The species-specified top-down method can help improve the quality of these emission inventories
Analysis of long-term observations of NOx and CO in megacities and application to constraining emissions inventories
Long-term atmospheric NOx/CO enhancement ratios in megacities provide evaluations of emission inventories. A fuel-based emission inventory approach that diverges from conventional bottom-up inventory methods explains 1970–2015 trends in NOx/CO enhancement ratios in Los Angeles. Combining this comparison with similar measurements in other U.S. cities demonstrates that motor vehicle emissions controls were largely responsible for U.S. urban NOx/CO trends in the past half century. Differing NOx/CO enhancement ratio trends in U.S. and European cities over the past 25 years highlights alternative strategies for mitigating transportation emissions, reflecting Europe's increased use of light-duty diesel vehicles and correspondingly slower decreases in NOx emissions compared to the U.S. A global inventory widely used by global chemistry models fails to capture these long-term trends and regional differences in U.S. and Europe megacity NOx/CO enhancement ratios, possibly contributing to these models' inability to accurately reproduce observed long-term changes in tropospheric ozone
Patients' preferences for fracture risk communication: the Risk Communication in Osteoporosis (RICO) study.
peer reviewed[en] UNLABELLED: The RICO study indicated that most patients would like to receive information regarding their fracture risk but that only a small majority have actually received it. Patients globally preferred a visual presentation of fracture risk and were interested in an online tool showing the risk.
PURPOSE: The aim of the Risk Communication in Osteoporosis (RICO) study was to assess patients' preferences regarding fracture risk communication.
METHODS: To assess patients' preferences for fracture risk communication, structured interviews with women with osteoporosis or who were at risk for fracture were conducted in 11 sites around the world, namely in Argentina, Belgium, Canada at Hamilton and with participants from the Osteoporosis Canada Canadian Osteoporosis Patient Network (COPN), Japan, Mexico, Spain, the Netherlands, the UK, and the USA in California and Washington state. The interviews used to collect data were designed on the basis of a systematic review and a qualitative pilot study involving 26 participants at risk of fracture.
RESULTS: A total of 332 women (mean age 67.5 ± 8.0 years, 48% with a history of fracture) were included in the study. Although the participants considered it important to receive information about their fracture risk (mean importance of 6.2 ± 1.4 on a 7-point Likert scale), only 56% (i.e. 185/332) had already received such information. Globally, participants preferred a visual presentation with a traffic-light type of coloured graph of their FRAX® fracture risk probability, compared to a verbal or written presentation. Almost all participants considered it important to discuss their fracture risk and the consequences of fractures with their healthcare professionals in addition to receiving information in a printed format or access to an online website showing their fracture risk.
CONCLUSIONS: There is a significant communication gap between healthcare professionals and patients when discussing osteoporosis fracture risk. The RICO study provides insight into preferred approaches to rectify this communication gap
Computational investigation of CO adsorbed on Aux, Agx and (AuAg)x nanoclusters (x = 1 − 5, 147) and monometallic Au and Ag low-energy surfaces
Patients' preferences for fracture risk communication: the Risk Communication in Osteoporosis (RICO) study.
The RICO study indicated that most patients would like to receive information regarding their fracture risk but that only a small majority have actually received it. Patients globally preferred a visual presentation of fracture risk and were interested in an online tool showing the risk. The aim of the Risk Communication in Osteoporosis (RICO) study was to assess patients' preferences regarding fracture risk communication. To assess patients' preferences for fracture risk communication, structured interviews with women with osteoporosis or who were at risk for fracture were conducted in 11 sites around the world, namely in Argentina, Belgium, Canada at Hamilton and with participants from the Osteoporosis Canada Canadian Osteoporosis Patient Network (COPN), Japan, Mexico, Spain, the Netherlands, the UK, and the USA in California and Washington state. The interviews used to collect data were designed on the basis of a systematic review and a qualitative pilot study involving 26 participants at risk of fracture. A total of 332 women (mean age 67.5 ± 8.0 years, 48% with a history of fracture) were included in the study. Although the participants considered it important to receive information about their fracture risk (mean importance of 6.2 ± 1.4 on a 7-point Likert scale), only 56% (i.e. 185/332) had already received such information. Globally, participants preferred a visual presentation with a traffic-light type of coloured graph of their FRAX® fracture risk probability, compared to a verbal or written presentation. Almost all participants considered it important to discuss their fracture risk and the consequences of fractures with their healthcare professionals in addition to receiving information in a printed format or access to an online website showing their fracture risk. There is a significant communication gap between healthcare professionals and patients when discussing osteoporosis fracture risk. The RICO study provides insight into preferred approaches to rectify this communication gap. [Abstract copyright: © 2023. The Author(s).
Problems encountered by the junior radiologic technology students during thesis writing
The descriptive method of research was employed in this study. It involved 95 junior radiologic technology students of De La Salle - Health Sciences Campus and they were chosen using stratified random sampling. An adapted questionnaire was employed to gather the needed data. This statistical treatments used were chi-square, frequency, mean, percentage, standard deviation and t-test of independent means. From the findings, the following conclusions were drawn: (1) Most of the respondents were male; (2) Most of them belonged to a family bracket whose monthly income of parents is over P30,000 but not more than P70,000; (3) In relation to choice of topic, development statistical test was the most problematic; (4) In relation to the adviser, consultation schedule was the most problematic; (5) In relation to library facilities and resources, availability of reference sources was the most problematic; (6) In relation to mechanics, forms and style in writing thesis and forms of documentation was the most problematic. In relation to colloquium, panel member was the most problematic
The relationship between management support system and the job satisfaction among radiologic technologists of De La Salle University Medical Center
The study utilized the descriptive research method in identifying and analyzing existing situations affecting the study. Using purposive sampling, a total of 20 radiologic technologists were included as respondents. A revised questionnaire was employed as the research instrument. Mean, standard deviation and Pearson Product-Moment Coefficient (r) were used to analyze data. Based on the findings, the following conclusions were drawn: (1) The overall level of radiology management support system implemented by the radiology administrators on the technologists of De La Salle University Medical Center falls under often. De La Salle University Medical Center provides support systems and gives much emphasis to the organizational structure, professional practice and professional development of their technologists; (2) Technologists perceived their level of job satisfaction as generally satisfactory. As observed, good salaries, fair working conditions and the support they get from their co-workers, chief technologists and radiologic administrators are considered to be the sources of job satisfaction. They believed that advancement in the job would be vital by building esteem so they could take advantage of opportunities that move them beyond the safety level to higher levels of professional achievement; (3) There was a strong positive linear relationship between the radiology management support system implemented by the radiology administrators and the job satisfaction of the radiologists of DLSUMC in terms of organizational structure, professional practice, management style, quality of leadership and professional development
The video game habits of fourth year high school students of the top feeder schools of the College of Medical Radiation Technology De La Salle Health Sciences Institute
The demographic data used was gender, daily allowance and type of family. This study gauged the extent of involvement of the fourth year high school students in playing video games and evaluated the side effects of playing video games using the descriptive method of research. The survey was accomplished using an adopted questionnaire from the research entitled “Addictive for whom? Electronic games, the third-person effect, and contributors to attitude toward addiction.” Some questions were removed from the original instrument since it is not applicable in the study. The respondents of the study included the whole population of the fourth year high school students of selected feeder schools of the College of Medical Radiation Technology of the De La Salle Health Sciences Institute. A total of 184 respondents were included in the study. The statistical data was computed using frequency, percentage, mean, median, standard deviation, range, ANOVA, independent t-test, Mann-Whitney test and Kruskal-Wallis test. Results showed that (1) majority of the respondents is female, belonged to the nuclear type of family and have daily allowance of 50 to 99 pesos; (2) the games have somewhat negative effect on their school performance and aspects of their lives. The respondents are less productive when they spend more time playing video games; (3) there is a significant difference in the video game habits of the respondents when grouped according to gender; (4) there is a significant difference in the video gaming habits of the respondents when grouped according to daily allowance; (5) there is no significant difference in the video gaming habits of the respondents in terms of frequency of playing and time taken away from other activities when grouped according to type of family. There is no significant difference in number of hours played, its importance as a leisure activity and evaluation of own level of addiction of the respondents
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