This study presents the first experimental investigation of date palm (Phoenix dactylifera) waste fast pyrolysis in a bubbling fluidized bed reactor. The physiochemical characteristics of the feedstock (from cultivars grown in the Emirate of Sharjah in the UAE), including three anatomical parts of the plant, namely, leaves, leaf stems and empty fruit bunches, have been first analyzed and compared to other popular type of biomass. These components have been subjected to fast pyrolysis and mass balances have been derived. The fast pyrolysis products (bio-oil, and non-condensable gas) have been analyzed in terms of their chemical composition, thermogravimetric profiles, and energy content. The overall product distribution in mass percentage at the pyrolysis temperature of 525 ºC was found to be 38.8% bio-oil (including 10.4% reaction water), 37.2% biochar and 24.0% non-condensable gas. The overall energy conversion efficiency (ratio of energy content in the product to that in the feedstock) was found to be 87.0%, thus indicative of the good potential of converting the date palm waste to energy while eliminating the negative environmental impact and cost associated with waste disposal.
Introduction
Non-cigarette tobacco products are an increasing public health concern globally. Little is known about midwakh, a pipe indigenous to the United Arab Emirates (UAE). This study aimed to assess the prevalence, attitudes, behaviours and policy evaluation of midwakh smoking among 13 to 15 year olds in the UAE.
Methods
We conducted secondary analyses of the 2013 UAE Global Youth Tobacco Survey. The main three outcomes were ever use, current use (past-30 days), and the number of midwakhs smoked per day. We assessed cessation, attitude, and policy measures. Regression models identified the association between each outcome measure and sex, school grade, nationality, weekly spending money, cigarette use, and parent and peer tobacco use.
Results
The prevalence of ever and current midwakh use were 18.5% and 9.0%, respectively. Daily midwakh users smoked a median of 8.0 per day while non-daily users smoked 3.8 per month. Higher midwakh prevalence was reported among wealthier males, older age groups, concurrent cigarette users and among participants having peers or parents who use tobacco. There was also variation by nationality. Reduced harm perception was greater among midwakh users than non-users. About 39.6% reported being declined a midwakh purchase due to age, and 35.5% reported noticing health warnings on packages.
Conclusions
Midwakh use is prevalent among 13 to 15 year olds in the UAE, and burden lies mainly with daily users. Further needed research should not delay implementation and evaluation of policies known to curb tobacco use among youth, including taxation, media campaigns, and provision of cessation services.
Waterpipe tobacco smoking (WPS) continues to spread globally and presents serious health hazards. The aim of the present study was to investigate the effects of treatment with WPS condensate (WPSC) on lung cell proliferation and plasticity as well as tumor cell recognition and killing by natural killer (NK) cells using cytotoxicity assays. The results indicated that exposure of normal and cancer lung cell lines to WPSC resulted in a decrease in their
in vitro
growth in a dose-dependent manner and it induced tumor senescence. In addition, WPSC selectively caused DNA damage as revealed by an increase in γH2AX and 53BP1 in tumor lung cells. To gain further insight into the molecular mechanisms altered by WPSC, we conducted a global comprehensive transcriptome analysis of WPSC-treated tumor cells. Data analysis identified an expression profile of genes that best distinguished treated and non-treated cells involving several pathways. Of these pathways, we focused on those involved in epithelial to mesenchymal transition (EMT) and stemness. Results showed that WPSC induced an increase in
SNAI2
expression associated with EMT,
ACTA2
and
SERPINE2
were involved in invasion and
CD44
was associated with stemness. Furthermore, WPSC exposure increased the expression of inflammatory response genes including
CASP1, IL1B, IL6
and
CCL2
. While immune synapse formation between NK and WPSC-treated lung cancer target cells was not affected, the capacity of NK cells to kill these target cells was reduced. The data reported in the present study are, to the best of our knowledge, the first
in vitro
demonstration of WPSC effects on lung cellular parameters providing evidence of its potential involvement in tumor physiology and development.
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