Expansion of the feedstock base for the production of diesel fuel by involving the heavy fractions and cold flow improvers

In this paper, the viability of expanding the feedstock base of diesel fuel production by the involvement of the heavy diesel fraction and the use of cold flow improvers was shown. The influence of the heavy diesel fraction content in the diesel fuel composition on its low-temperature properties and the effectiveness of the cold flow improver were studied. It was established that the involvement of a small amount of the heavy diesel fraction (up to 3 vol%) increases the effectiveness of the cold flow improver in relation to the cold filter plugging point. The following recipes of diesel fuel production were recommended: the involvement of up to 5 vol% heavy diesel fraction allows producing fuel of the summer grade; the involvement of up to 5 vol% heavy diesel fraction and the cold flow improver allows producing fuel of the inter-season grade; and the involvement of up to 3 vol% heavy diesel fraction and the cold flow improver to produce fuel of the winter grade

The COVID-19 pandemic and its global effects on dental practice : An International survey

Objectives: A multicentre survey was designed to evaluate the impact of COVID-19 outbreak on dental practice worldwide, estimate the COVID-19 related symptoms/signs, work attitudes and behaviour and the routine use of protective measures and Personal Protective Equipment (PPE). Methods: A global survey using a standardized questionnaire with research groups from 36 countries was designed. The questionnaire was developed and pretested during April 2020 and contained three domains: 1) Personal data; 2) COVID-19 positive rate and symptoms/signs presumably related to the coronavirus; 3) Working conditions and PPE adopted after the outbreak. Countries' data were grouped by the Country Positive Rate (CPR) during the survey period and by Gross-National-Income per capita. An ordinal multinomial logistic regression model was carried out with COVID-19 self-reported rate referred by dental professionals as dependent variable to assess the association with questionnaire items. Results: A total of 52,491 questionnaires were returned with a male/female ratio of 0.63. Out of the total respondents, 7,859 dental professionals (15%) reported symptoms/signs compatible with COVID-19. More than half of the sample (n = 27,818; 53%) stated to use FFP2/N95 masks, while 21,558 (41.07%) used eye protection. In the bivariate analysis, CPR and N95/FFP2 were significantly associated (OR = 1.80 95% =5.20 95% 95% CI = 1.60/2.82 and OR CI = 1.44/18.80, respectively), while Gross-National-Income was not statistically associated with CPR (OR = 1.09 CI = 0.97/1.60). The same significant associations were observed in the multivariate analysis. Conclusions: Oral health service provision has not been significantly affected by COVID-19, although access to routine dental care was reduced due to country-specific temporary lockdown periods. While the dental profession has been identified at high-risk, the reported rates of COVID-19 for dental professionals were not significantly different to those reported for the general population in each country. These findings may help to better plan oral health care for future pandemic events