Objective: To determine the prevalence of migraine and
its associated factors in students at the University of Parakou. Methods: It
was a cross-sectional study carried out from February 1st to April 30th 2011.
It included all students registered during the academic year 2010-2011 and
selected by systematic random sampling.
Migraine was defined according to IHS 2004 criteria. To assess the link
between migraine and body mass index we collected height and weight of each
student. Multivariate analysis was used to study the factors associated with
migraine, odds-ratio and their confidence interval were estimated. SPSS Soft-ware
was used to perform statistical analysis. Results: During the study period
1200, students returned their questionnaires. They were 842 males and 358
females. 171 fulfilled migraine criteria, and the overall prevalence of
migraine was 14.2% (CI 95%: 11.6% - 17.4%). The main associated factors were
the sex with an OR: 2.3 (CI 95%: 1.6 - 3.2) and family history of headache with
an OR: 1.6 (CI 95%: 1.1 - 2.4). Migraine with aura was the frequent form
(59.1%) and visual aura the frequent form of aura. No association was found
between migraine and body mass index but students with obesity had high risk of
migraine with aura OR: 3.8 (CI 95%: 1.5 - 9.7) compared with those with normal
weight. The main triggering factors were sleeplessness (90.1%) and mental
fatigue (85.4%). Conclusion: The results suggest a high prevalence of migraine
among students at Parakou University and no association between obesity and migraine.
The 8-node iso-parametric thin shell element was employed in the study of stress concentrations in the welded tubular “K” joint. Element equilibrium equations were derived using isoparametric formulation based on thin shell theory. After assembly, the resulting system equations were solved using existing fortran programs. Numerical experiments were conducted to isolate and locate ideal gap (positions) for the two braces of the “K” joint. The nominal stresses were calculated from which stress concentration factors were obtained. The resulting stress concentration factors were presented both as tables and as figures. A good agreement between our solutions and those for model joints in the literature is good and acceptable. It was found that the wider apart the brace spacing is, the weaker the strength of the joint. It was also found that the best location for the braces occurs when the stress level changes sign either from positive to negative or vice versa at a critical sampling point.
Calcified rock-forming marine filamented benthic micro- and macrophytes of Dzhelindia Kolosov, 1970 (Figure 1(а)) and Chaptchaica Kolosov, 1975 (Figure 1(b)) genera, thrived in Neoproterozoic (1000-541 million years ago) Siberia together with cyanobacteria. Their belonging to Rhodophyta is well-grounded. These and other Neoproterozoic rodofits, as well as Epiphyton Bornemann 1886 (Figure 1(c)) and other Early Cambrian (541-513 million years ago) benthic algae, oxygenating floor of epicontinental sea basin, formed conditions, favorable for the animals. In combination with other biotic, and such abiotic factors as: equatorial position and tectonic feature of Siberian platform; volcanism; transgression of the sea; diversity of ecologic niches, these conditions were prerequisites of skeleton and shell acquisition by Early Cambrian animals, and as a consequence, accelerated morphologic evolution, increased diversity of taxons of different groups of animals.
The gross alpha (α)
and beta (β) activities and trace heavy elemental concentrations have
been determined in Single Super Phosphate
(SSP) and Nitrogen Phosphorous Potassium (NPK) fertilizers samples used
for agricultural purposes in Nigeria. Cultivated farm soil samples from two
regions (north and south) in the country and samples of phosphate rocks were
also analyzed for gross α and β radioactivity and elemental
concentrations. The beta activity concentration in the NPK (15-15-15)
fertilizers was found to vary from 2410.0 ± 80.0 Bq·kg–1 to 4560 ± 140.0 Bq·kg–1, between 1340.0 ± 70.0 Bq·kg–1 and 1440.0 ± 70.0 Bq