51 research outputs found

    ASSESSING THE CONTRIBUTION OF THE MAIN EMISSION SOURCES TO PARTICULATE MATTER CONCENTRATIONS IN THE MILAN AREA

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    On the basis of CityDelta III project input dataset, the CAMx chemical and transport Eulerian model has been applied over a 300x300 km2 domain focused on the Milan area (Northern part of Italy) for the whole 2004. Model results have been analysed by mean of the Source Apportionment technique at the Milan receptor, in order to discriminate the contribution of several key emission sectors, also distinguishing the most emitting area of Milan from the surroundings. Obtained results highlight that road transport is the most relevant sector, followed by agriculture and domestic heating. The source apportionment analysis also revealed that more than 70% of the PM10 is due to emissions outside of Milan

    Source apportionment to support air quality management practices: A fitness-for-purpose guide (V 3.1)

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    Information on the origin of pollution constitutes an essential step of air quality management as it helps identifying measures to control air pollution. In this document, we review the most widely used source-apportionment methods for air quality management. Using simple theoretical examples we highlight the differences among these methods and explain why and under which circunstances they lead to different results and therefore different conclusions in the context of air quality management. These differences are a consequence of the intrinsic assumptions that underpin the different methodologies and determine/limit their range of applicability. We show that ignoring their underlying assumptions is a risk for efficient/successful air quality management as these methods are sometimes used beyond their scope and range of applicability. The simplest approach based on increments, contributions obtained through receptor models or tagging approaches built in air quality models as well impacts obtained via “brute-force” methods are discussed. The guide is organised as follows: the different source apportionment approaches and their associated properties are presented in Part I, simple examples are introduced in Part II to illustrate the main differences in terms of results while Part III focuses on the fitness-for-purpose aspects of the different methods. Finally Part IV lists and briefly discusses a series of open issues.JRC.C.5-Air and Climat

    Comparison of source apportionment approaches and analysis of non-linearity in a real case model application

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    Abstract. The response of particulate matter (PM) concentrations to emission reductions was analysed by assessing the results obtained with two different source apportionment approaches. The brute force (BF) method source impacts, computed at various emission reduction levels using two chemical transport models (CAMx and FARM), were compared with the contributions obtained with the tagged species (TS) approach (CAMx with the PSAT module). The study focused on the main sources of secondary inorganic aerosol precursors in the Po Valley (northern Italy): agriculture, road transport, industry and residential combustion. The interaction terms between different sources obtained from a factor decomposition analysis were used as indicators of non-linear PM10 concentration responses to individual source emission reductions. Moreover, such interaction terms were analysed in light of the free ammonia / total nitrate gas ratio to determine the relationships between the chemical regime and the non-linearity at selected sites. The impacts of the different sources were not proportional to the emission reductions, and such non-linearity was most relevant for 100 % emission reduction levels compared with smaller reduction levels (50 % and 20 %). Such differences between emission reduction levels were connected to the extent to which they modify the chemical regime in the base case. Non-linearity was mainly associated with agriculture and the interaction of this source with road transport and, to a lesser extent, with industry. Actually, the mass concentrations of PM10 allocated to agriculture by the TS and BF approaches were significantly different when a 100 % emission reduction was applied. However, in many situations the non-linearity in PM10 annual average source allocation was negligible, and the TS and BF approaches provided comparable results. PM mass concentrations attributed to the same sources by TS and BF were highly comparable in terms of spatial patterns and quantification of the source allocation for industry, transport and residential combustion. The conclusions obtained in this study for PM10 are also applicable to PM2.5

    Analysis of meteorology-chemistry interactions during air pollution episodes using online coupled models within AQMEII Phase-2

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    This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).This study reviews the top ranked meteorology and chemistry interactions in online coupled models recommended by an experts’ survey conducted in COST Action EuMetChem and examines the sensitivity of those interactions during two pollution episodes: the Russian forest fires 25 Jul -15 Aug 2010 and a Saharan dust transport event from 1 Oct -31 Oct 2010 as a part of the AQMEII phase-2 exercise. Three WRF-Chem model simulations were performed for the forest fire case for a baseline without any aerosol feedback on meteorology, a simulation with aerosol direct effects only and a simulation including both direct and indirect effects. For the dust case study, eight WRF-Chem and one WRF-CMAQ simulations were selected from the set of simulations conducted in the framework of AQMEII. Of these two simulations considered no feedbacks, two included direct effects only and five simulations included both direct and indirect effects. The results from both episodes demonstrate that it is important to include the meteorology and chemistry interactions in online-coupled models. Model evaluations using routine observations collected in AQMEII phase-2 and observations from a station in Moscow show that for the fire case the simulation including only aerosol direct effects has better performance than the simulations with no aerosol feedbacks or including both direct and indirect effects. The normalized mean biases are significantly reduced by 10-20% for PM10 when including aerosol direct effects. The analysis for the dust case confirms that models perform better when including aerosol direct effects, but worse when including both aerosol direct and indirect effects, which suggests that the representation of aerosol indirect effects needs to be improved in the model.Peer reviewedFinal Published versio

    Varieties of Capitalism and the Learning Firm: Contemporary Developments in EU and German Company Law - A Comment on the Strine-Bainbridge Debate About Shared Values of Corporate Management and Labor

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    Research in corporate governance and in labour law has been characterized by a disjuncture in the way that scholars in each field are addressing organizational questions related to the business enterprise. While labour has eventually begun to shift perspectives from aspirations to direct employee involvement in firm management, as has been the case in Germany, to a combination of \u27exit\u27 and \u27voice\u27 strategies involving pension fund management and securities litigation, it remains to be seen whether this new stream will unfold as a viable challenge to an otherwise exclusionary shareholder value paradigm. At the same time, recent suggestions made by Delaware Chancery Court Vice Chancellor Strine, to dare think about potentially shared commitments between management and labor - and UCLA\u27s Stephen Bainbridge\u27s response - underline the viability - and, the contestedness - of attempts at moving the corporate governance debate beyond the confines of corporate law proper. While such a wider view had already famously been encouraged by Dean Clarke in his 1986 treatise on Corporate Law (p. 32), mainstream corporate law does not seem to have endorsed this perspective. This paper takes the questionable divide between management and labor within the framework of a limiting corporate governance concept as starting point to explore the institutional dynamics of the corporation, hereby building on the theory of the innovative enterprise, as developed by management theorists Mary O\u27Sullivan and William Lazonick. Largely due to the sustained distance between corporate and labour law scholars, neither group has effectively addressed their common blind spot: a better understanding of the business enterprise itself. In midst of an unceasing flow of affirmations of the finance paradigm of the corporation on the one hand and \u27voice\u27 strategies by labour on the other, it seems to fall to management theorists to draw lessons from the continuing co-existence of different forms of market organization, in which companies appear to thrive. Exploring the conundrum of \u27risky\u27 business decisions within the firm, management theorists have been arguing for the need to adopt a more sophisticated organizational perspective on companies operating on locally, regionally and transnationally shaped, often highly volatile market segments. Research by comparative political economists has revealed a high degree of connectivity between corporate governance and economic performance without, however, arriving at such favourable results only for shareholder value regimes. Such findings support the view that corporate governance regimes are embedded in differently shaped regulatory frameworks, characterized by distinct institutions, both formal and informal, and enforcement processes. As a result of these findings, arguments to disassociate issues of corporate governance from those of the firm\u27s (social) responsibility [CSR] have been losing ground. Instead, CSR can be taken to be an essential part of understanding a particular business enterprise. It is the merging of a comparative political economy perspective on the corporation with one on the organizational features, structures and processes of the corporation, which can help us better understand the distribution of power and knowledge within the \u27learning firm\u27

    Results of the first European Source Apportionment intercomparison for Receptor and Chemical Transport Models

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    In this study, the performance of the source apportionment model applications were evaluated by comparing the model results provided by 44 participants adopting a methodology based on performance indicators: z-scores and RMSEu, with pre-established acceptability criteria. Involving models based on completely different and independent input data, such as receptor models (RMs) and chemical transport models (CTMs), provided a unique opportunity to cross-validate them. In addition, comparing the modelled source chemical profiles, with those measured directly at the source contributed to corroborate the chemical profile of the tested model results. The most used RM was EPA- PMF5. RMs showed very good performance for the overall dataset (91% of z-scores accepted) and more difficulties are observed with SCE time series (72% of RMSEu accepted). Industry resulted the most problematic source for RMs due to the high variability among participants. Also the results obtained with CTMs were quite comparable to their ensemble reference using all models for the overall average (>92% of successful z-scores) while the comparability of the time series is more problematic (between 58% and 77% of the candidates’ RMSEu are accepted). In the CTM models a gap was observed between the sum of source contributions and the gravimetric PM10 mass likely due to PM underestimation in the base case. Interestingly, when only the tagged species CTM results were used in the reference, the differences between the two CTM approaches (brute force and tagged species) were evident. In this case the percentage of candidates passing the z-score and RMSEu tests were only 50% and 86%, respectively. CTMs showed good comparability with RMs for the overall dataset (83% of the z-scores accepted), more differences were observed when dealing with the time series of the single source categories. In this case the share of successful RMSEu was in the range 25% - 34%.JRC.C.5-Air and Climat

    Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

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    Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

    Integration of oncology and palliative care : a Lancet Oncology Commission

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    Full integration of oncology and palliative care relies on the specific knowledge and skills of two modes of care: the tumour-directed approach, the main focus of which is on treating the disease; and the host-directed approach, which focuses on the patient with the disease. This Commission addresses how to combine these two paradigms to achieve the best outcome of patient care. Randomised clinical trials on integration of oncology and palliative care point to health gains: improved survival and symptom control, less anxiety and depression, reduced use of futile chemotherapy at the end of life, improved family satisfaction and quality of life, and improved use of health-care resources. Early delivery of patient-directed care by specialist palliative care teams alongside tumour-directed treatment promotes patient-centred care. Systematic assessment and use of patient-reported outcomes and active patient involvement in the decisions about cancer care result in better symptom control, improved physical and mental health, and better use of health-care resources. The absence of international agreements on the content and standards of the organisation, education, and research of palliative care in oncology are major barriers to successful integration. Other barriers include the common misconception that palliative care is end-of-life care only, stigmatisation of death and dying, and insufficient infrastructure and funding. The absence of established priorities might also hinder integration more widely. This Commission proposes the use of standardised care pathways and multidisciplinary teams to promote integration of oncology and palliative care, and calls for changes at the system level to coordinate the activities of professionals, and for the development and implementation of new and improved education programmes, with the overall goal of improving patient care. Integration raises new research questions, all of which contribute to improved clinical care. When and how should palliative care be delivered? What is the optimal model for integrated care? What is the biological and clinical effect of living with advanced cancer for years after diagnosis? Successful integration must challenge the dualistic perspective of either the tumour or the host, and instead focus on a merged approach that places the patient's perspective at the centre. To succeed, integration must be anchored by management and policy makers at all levels of health care, followed by adequate resource allocation, a willingness to prioritise goals and needs, and sustained enthusiasm to help generate support for better integration. This integrated model must be reflected in international and national cancer plans, and be followed by developments of new care models, education and research programmes, all of which should be adapted to the specific cultural contexts within which they are situated. Patient-centred care should be an integrated part of oncology care independent of patient prognosis and treatment intention. To achieve this goal it must be based on changes in professional cultures and priorities in health care
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