this study investigated the prevalence rates of migrine and tension-type headaches among the students of Shiraz university of medical sciences during the academic year 1996-1997.the study was carried out cross-sectionally on a representative random sample of 310 students selected systematically.A semi structured questionnaire was used to screen headache among the students,applying the internati...

a new method for the determination of trace copper(ii) in food samples by cloud point extraction(cpe) combined with flame atomic absorption spectrometry(faas) is presented and evaluated. the method is based on the fact that hydrophobic complex of copper(ii) with sodium diethyldithiocarbamate (ddtc) was formed at ph 6.0 and subsequently the hydrophobic complex was extracted into surfactant-rich ...

Zircon (ZrSiO4) is a small mineral highly resistant to chemical changes; this robustness has led it to be used for estimating earth conditions eons ago. It has been used to date geologic events, measuring its radiogenic Pb, U and Th isotopes. The oldest dated mineral on Earth is a zircon from Australia, and its oxygen isotope value suggests Earth’s crust was cool and wet as long ago as 4.3 bill...

Beckettite (Ca2V6Al6O20; IMA 2015-001) is a newly discovered refractory mineral, occurring as micrometer-sized grains intergrown with hibonite and perovskite, surrounded by secondary grossular, anorthite, coulsonite, hercynite, corundum. It occurs within highly altered areas in V-rich, Type A Ca-Al-rich inclusion (CAI), A-WP1, from the Allende CV3 carbonaceous chondrite. The type beckettite has...

Modelling the reservoirs and fluxes of Zn in Earth's crust mantle requires data on solubility its mineral hosts ores coexisting fluids, as well complexation these fluids a function fluid composition, pressure, temperature. However, due to experimental challenges, availability such is limited pressures below 1 GPa, which are only representative upper conditions. Here, we report effects salinity ...

Olivine is a major mineral in ultramafic and mafic rocks. Due to the higher Mg/Fe partition coefficient of olivine than coexisting phases, occurrences Mg–poorer grains, especially with Mg#[= Mg/(Mg + Fe2+)] = 0.2–0.6, are rarely reported, thus, their spectroscopic data limited. Fe–rich phenocrysts showing compositional zoning Mg# ~ 0.5 (core) 0.3 (rim) microphenocrysts 0.4 0.2 occur basaltic tr...