150 research outputs found
Association of waterpipe smoking and road traffic crashes
<p>Abstract</p> <p>Background</p> <p>The purpose of this research was to examine whether waterpipe smokers experience increased risk of motor vehicle crashes.</p> <p>Methods</p> <p>In a telephone survey, a random sample of Iranian drivers were asked to report their age, gender, vehicle age, whether their vehicles were equipped with anti-lock braking system (ABS), average daily drive time (DDT), whether they smoked cigarette or waterpipe, whether they had diabetes mellitus (DM), number of traffic crashes during the last calendar year and whether the crash involved a pedestrian or another vehicle.</p> <p>Results</p> <p>A total of 2070 motor vehicle owners with the mean age of 41.6 ± 11.45 were interviewed. The annual incidence of Road Traffic Crashes (RTC) was 14.9%; 14.0% involved a collision/s with other vehicles and 0.9% with pedestrians. There was an association between the RTC and male gender, DDT, being a cigarette smoker, being a waterpipe smoker and DM in univariable analysis. The association between RTC and being a waterpipe smoker and also cigarette smoker was significant in multivariable analysis after adjustment for DDT.</p> <p>Conclusions</p> <p>Being waterpipe and/or cigarette smoker and DDT were the independent predictors of the number of traffic crashes in Poisson regression model. If the increased risk of RTC among waterpipe or cigarette smokers is seen in other studies, it would be beneficial to promote tobacco cessation and control strategies through injury prevention initiatives.</p
A Fear-Inducing Odor Alters PER2 and c-Fos Expression in Brain Regions Involved in Fear Memory
Evidence demonstrates that rodents learn to associate a foot shock with time of day, indicating the formation of a fear related time-stamp memory, even in the absence of a functioning SCN. In addition, mice acquire and retain fear memory better during the early day compared to the early night. This type of memory may be regulated by circadian pacemakers outside of the SCN. As a first step in testing the hypothesis that clock genes are involved in the formation of a time-stamp fear memory, we exposed one group of mice to fox feces derived odor (TMT) at ZT 0 and one group at ZT 12 for 4 successive days. A separate group with no exposure to TMT was also included as a control. Animals were sacrificed one day after the last exposure to TMT, and PER2 and c-Fos protein were quantified in the SCN, amygdala, hippocampus, and piriform cortex. Exposure to TMT had a strong effect at ZT 0, decreasing PER2 expression at this time point in most regions except the SCN, and reversing the normal rhythm of PER2 expression in the amygdala and piriform cortex. These changes were accompanied by increased c-Fos expression at ZT0. In contrast, exposure to TMT at ZT 12 abolished the rhythm of PER2 expression in the amygdala. In addition, increased c-Fos expression at ZT 12 was only detected in the central nucleus of the amygdala in the TMT12 group. TMT exposure at either time point did not affect PER2 or c-Fos in the SCN, indicating that under a light-dark cycle, the SCN rhythm is stable in the presence of repeated exposure to a fear-inducing stimulus. Taken together, these results indicate that entrainment to a fear-inducing stimulus leads to changes in PER2 and c-Fos expression that are detected 24 hours following the last exposure to TMT, indicating entrainment of endogenous oscillators in these regions. The observed effects on PER2 expression and c-Fos were stronger during the early day than during the early night, possibly to prepare appropriate systems at ZT 0 to respond to a fear-inducing stimulus
An experimental test of hostâs life history traits modulation in response to cuckoo parasitism risk
Hosts can counteract parasites through defences based on resistance and/or tolerance.
The mechanistic basis of tolerance, which involve defensive mechanisms minimizing parasite
damage after a successful parasitic attack, remains poorly explored in the study of
cuckoo-host interactions. Here, we experimentally explore the possibility that the risk of
great spotted cuckoo Clamator glandarius parasitism may induce tolerance defences in
magpie Pica pica hosts through plasticity in life-history traits. We predict that magpies
exposed to auditory cues indicating high parasitism risk will more likely exhibit resistance
and/or modify their life-history traits to minimize parasitism costs (i.e. tolerance) compared
to magpies under low parasitism risk. We found that manipulating the perceived parasitism
risk did not affect host resistance (i.e. rejection of parasitic eggs) nor host life-history traits.
Unexpectedly, host's egg volume increased over the season in nests exposed to auditory
cues of control non-harmful hoopoes Upupa epops. Our results do not provide support for
inducible defences (either based on resistance or tolerance) in response to risk of parasitism
in magpie hosts. Even so, we encourage studying plastic expression of breeding strategies
in response to risk of cuckoo parasitism to achieve a better understanding of the mechanistic
basis of tolerance defences.This work was supported by the Spanish
Ministry of Education and Science/FEDER (Projects
CGL2011-27561/BOS and CGL2014-56769-P to D.
P. and J.M.A.). D.P. was supported by the
Government of Extremadura while writing (contract
number TA13002). M.E.G. was supported by the
Spanish Ministry of Economy and Competitiveness
(grant number BES-2012-051898).
Catalysing sustainable fuel and chemical synthesis
Concerns over the economics of proven fossil fuel reserves, in concert with government and public acceptance of the anthropogenic origin of rising CO2 emissions and associated climate change from such combustible carbon, are driving academic and commercial research into new sustainable routes to fuel and chemicals. The quest for such sustainable resources to meet the demands of a rapidly rising global population represents one of this centuryâs grand challenges. Here, we discuss catalytic solutions to the clean synthesis of biodiesel, the most readily implemented and low cost, alternative source of transportation fuels, and oxygenated organic molecules for the manufacture of fine and speciality chemicals to meet future societal demands
Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications
Superparamagnetic iron oxide nanoparticles
can providemultiple benefits for biomedical applications
in aqueous environments such asmagnetic separation or
magnetic resonance imaging. To increase the colloidal
stability and allow subsequent reactions, the introduction
of hydrophilic functional groups onto the particlesâ
surface is essential. During this process, the original
coating is exchanged by preferably covalently bonded
ligands such as trialkoxysilanes. The duration of the
silane exchange reaction, which commonly takes more
than 24 h, is an important drawback for this approach. In
this paper, we present a novel method, which introduces
ultrasonication as an energy source to dramatically
accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove
the generic character, different functional groups were
introduced on the surface including polyethylene glycol
chains, carboxylic acid, amine, and thiol groups. Their
colloidal stability in various aqueous buffer solutions as
well as human plasma and serum was investigated to
allow implementation in biomedical and sensing
applications.status: publishe
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