Current Covid-19 Impact On Saudi Stock Market: Evidence From An ARDL Model

oai:ojs2.www.ijafame.org:article/9This paper investigates the effect of COVID-19 pandemic on stock market in KSA applying an Autoregressive Distributed Lag (ARDL) cointegration approach. More especially, we analyze the relationship between the natural logarithm of trading volume of Tadawull All shares index (TASI) and the natural logarithm of daily COVID-19 confirmed cases both in the short-run and the long-run. The bounds test for cointegration is carried out for daily series over the period from March 02, 2020 till May 20, 2020.Toda-Yamamoto causality test is implemented between variables. Our findings indicate that there is a negative impact of COVID-19 on stock market only in the long-run. Causality test reveals a unidirectional causality from COVID-19 prevalence’s measure to stock market. Robustness check seems to be conclusive.This paper investigates the effect of COVID-19 pandemic on stock market in KSA applying an Autoregressive Distributed Lag (ARDL) cointegration approach. More especially, we analyze the relationship between the natural logarithm of trading volume of Tadawull All shares index (TASI) and the natural logarithm of daily COVID-19 confirmed cases both in the short-run and the long-run. The bounds test for cointegration is carried out for daily series over the period from March 02, 2020 till May 20, 2020.Toda-Yamamoto causality test is implemented between variables. Our findings indicate that there is a negative impact of COVID-19 on stock market only in the long-run. Causality test reveals a unidirectional causality from COVID-19 prevalence’s measure to stock market. Robustness check seems to be conclusive

Assessment of narghile (shisha, hookah) smokers' actual exposure to toxic chemicals requires further sound studies

Tobacco smoking is hazardous for health. However, not all forms of tobacco use entail the same risks and the latter should be studied and compared in a sound realistic way. Smoking machines for cigarettes (which are consumed in a few minutes) were early designed as a tool to evaluate the actual intake of toxic substances (‘toxicants’) by smokers. However, the yields (tar, nicotine, CO, etc.) provided by such machines poorly reflect the actual human smoking behaviour known to depend on numerous factors (anxiety, emotions, anthropological situation, etc.). In the case of narghile smoking, the problems are even more complex, particularly because of the much longer duration of a session. A recent study from the US-American University of Beirut was based on a field smoking topography and claimed consistency with a laboratory smoking machine. We offer a point by point critical analysis of such methods on which most of the ‘waterpipe’ antismoking literature since 2002 is based

Errors and misquotations in the study of shisha, blood pressure and heart rate in Jordan

Aim: This comment is based on a critical review of a study on blood pressure and heart rate in shisha (narghile, hookah) smokers in Jordan. Subjects and methods: The study was analysed against the most recent literature on this issue, in general, and against peer-reviewed biomedical publications from the Middle East, in particular. Results: Several errors and misquotations were found in the study under scrutiny. Most of them stem from misrepresentations related to the chemistry of shisha smoke, the anthropology and geography of its use, and the relevance of the literature cited by the authors (vs. the non-cited one), both from a quality and quantity viewpoint. Conclusion: A clarification is made about all these points of utmost importance and will hopefully help a new generation of researchers avoid wading too far in this field. Against the background of a world epidemic, public health interventions will gain credibility and performance

A critique of the WHO TobReg's "Advisory Note" report entitled: "Waterpipe tobacco smoking: health effects, research needs and recommended actions by regulators"

BACKGROUND AND AIM: The World Health Organisation Study Group on Tobacco Product Regulation (TobReg) has issued in 2005 an "Advisory Note" entitled: "Waterpipe Tobacco Smoking: Health Effects, Research Needs and Recommended Actions by Regulators". "Waterpipe" smoking is now considered a global public health threat and the corresponding artefact is actually known in the world under three main terms: hookah, narghile and shisha. This important report, the first ever prepared by WHO on the subject, poses two major problems. On one hand, its bibliographical references dismiss world chief relevant studies. On the other, it contains a certain number of errors of many orders: biomedical, sociological, anthropological and historical. The purpose of the present study is to highlight, one by one, where these weaknesses and errors lie and show how this official report can be considerably improved. RESULTS: We realise that widely advertised early anthropological studies were not taken into consideration whereas they shed a substantial light on this peculiar form of smoking and help understanding its high complexity. As for concrete errors to be found in this report, they deal with the chemistry of smoke, health-related effects, smoking patterns, description and history of the artefact and its use, gender and underage use aspects, prevention and research needs in this field. CONCLUSION: The scientific credibility of an international expert report may be at stake if its recommendations do not rely on sound objective research findings and a comprehensive review of the existing literature. The critical comments in this study will certainly help improve the present WHO report

Framework for Electric Vehicles and Photovoltaic Synergies

Historically road transport has been exclusively dominated by petrol and diesel engines. Both alternatives are proved to be unsustainable due to their environmental impacts and the limited nature of their primary resources. Today’s transportation sector in the European Union (EU) accounts for 23% of CO2 emissions, 72% of which is being emitted by road transport. The European Union’s CO2 emission regulation for new cars, has come as a response to set emission performance limits for new passenger cars with the goal of establishing a road map change for automotive sector. Furthermore, the EU has set challenging targets to reduce greenhouse gas emissions by 40% in 2030 (relative to emissions in 1990) and for energy consumed to be generated at least with 27% from renewable sources in 2030. As regards energy efficiency, the 2030 framework also indicated that the cost-effective delivery of the greenhouse gas emissions reduction target for 2030 would require increased energy savings of the order of 27%. The renewable energy directive particularly identified: technological innovation, energy efficiency and contribution of renewable energy sources in transport sector as one of the most effective tools in reaching the expected targets in terms of sustainability and security of the supply. In such context it is obvious that reaching these challenges will be certainly depending on the rollout of Electric Vehicles (EV) as a mean of sustainable transport, higher penetration of distributed renewable energy sources. One consequential challenge will consist in accommodating such paradigm in the most cost-efficient fashion through active involvement of customer and better flexibility of the demand. This report highlights the current trends and expected evolution in the EU in term of electromobility, Photovoltaic (PV) systems and smart grids, with the aim of identifying mutual synergies aiming at enabling: energy efficiency, sustainable transport and higher share of renewable energy sources in the final energy mix. A technical conceptual architecture for integration of EV facilities and distributed generation sources in the context of smart grid is proposed to identify the predictable penetration limits of PV systems and EV users.JRC.F.3-Energy Security, Systems and Marke

Hookah smoking and cancer: carcinoembryonic antigen (CEA) levels in exclusive/ever hookah smokers

<p>Abstract</p> <p>Background</p> <p>We have recently published some work on CEA levels in hookah (also called narghile, shisha elsewhere) and cigarette smokers. Hookah smokers had higher levels of CEA than non-smokers although mean levels were low compared to cigarette smokers. However some of them were also users of other tobacco products (cigarettes, bidis, etc.).</p> <p>Objectives</p> <p>To find serum CEA levels in ever/exclusive hookah smokers, i.e. those who smoked only hookah (no cigarettes, bidis, etc.), prepared between 1 and 4 times a day with a quantity of up to 120 g of a tobacco-molasses mixture each (i.e. the tobacco weight equivalent of up to 60 cigarettes of 1 g each) and consumed in 1 to 8 sessions.</p> <p>Methods</p> <p>Enhanced chemiluminescent immunometric technique was applied to measure CEA levels in serum samples from 59 exclusive male smokers with age ranging from 20–80 years (mean = 58.8 ± 14.7 years) and 8–65 years of smoking (mean = 37.7 ± 16.8). 36 non-smokers served as controls. Subjects were divided into 3 groups according to the number of preparations; the number of sessions and the total daily smoking time: Light (1; 1; ≤ 20 minutes); Medium (1–3; 1–3; >20 min to ≤ 2 hrs) and Heavy smokers (2–4; 3–8; >2 hrs to ≤ 6 hrs). Because of the nature of distribution of CEA levels among our individuals, Wilcoxon's rank sum two-sample test was applied to compare the variables.</p> <p>Results</p> <p>The overall CEA levels in exclusive hookah smokers (mean: 3.58 ± 2.61 ng/ml; n = 59) were not significantly different (p ≤ 0.0937) from the levels in non-smokers (2.35 ± 0.71 ng/ml). Mean levels in light, medium and heavy smokers were: 1.06 ± 0.492 ng/ml (n = 5); 2.52 ± 1.15 ng/ml (n = 28) and 5.11 ± 3.08 ng/ml (n = 26) respectively. The levels in medium smokers and non-smokers were also not significantly different (p ≤ 0.9138). In heavy smokers, the CEA levels were significantly higher than in non-smokers (p ≤ 0.0001567).</p> <p>Conclusion</p> <p>Overall CEA levels in exclusive hookah smokers were low compared to cigarette smokers. However, heavy hookah smoking substantially raises CEA levels. Low-nitrosamines smokeless tobacco of the SNUS Swedish type could be envisaged as an alternative to smoking for this category of users and also, in a broad harm reduction perspective, to the prevalent low-quality moist snuff called naswar.</p

Valorization of Date Palm Wastes by Lignin Extraction to be Used for the Improvement of Polymeric Membrane Characteristics

This work aimed to valorize Date Palm Wastes (DPW) by the extraction of lignin and its application for polymeric membrane modification. Lignin was extracted from five types of DPW (date palm kernel, leaflet, pedicel, palm frond, and fibrilium) using the Klason method. Following DPW characterization, we remark the highest amount of extractives content in the leaflet sample (10.07 %) and the lowest in the fibrilium sample (6.51 %). The ash content ranged from 1.56 % for fibrilium to 7.96 % for palm frond. After extraction, the lignin yield was in the range of 22–32 %. The extracted lignins were characterized by Infrared and Ultraviolet–visible spectroscopy. All extracted lignins provide a high concentration of (-OH) group. Besides, both syringyl and guaiacyl are present in the extracted lignins with a slightly more syringyl unit. The extracted lignins were added to the polymeric solution, prepared from waste plastic, to produce membranes. These membranes showed improved hydrophilicity marked a decrease in the contact angle of 28 % when the lignin concentration increased from 0.125 to 0.5 %. In addition, the membrane porosity increased with the use of the extracted lignins as an additive