Proxies for past seawater chemistry, such as Mg/Ca and Sr/Ca ratios, provide a record of the dynamic exchanges of elements between the solid Earth, the atmosphere, and the hydrosphere and the evolving influence of life. We estimated past oceanic Mg/Ca and Sr/Ca ratios from suites of 1.6- to 170-million-year-old calcium carbonate veins that had precipitated from seawater-derived fluids in ocean ...

to investigate uterine fluid and serum calcium (ca) and magnesium (mg) variations during the estrus cycle in water buffaloes, 71 genital tracts and blood samples were collected from the abattoir in urmia. the phase of the estrous cycle was determined by examining ovarian structures. 18 animals were pro-estrous, 15 estrous, 16 met-estrous and 22 diestrous. the uterine fluid was collected by gent...

Approaches to the design of recycling-tolerant Al-Zn-Mg alloys were formulated be achieved via combined Ca, Fe, and Si, appropriate solidification conditions heat treatment. A CalPhaD calculation experimental study employed for analysis Al-8%Zn-3%Mg alloy doped with 1–2%Ca, 0.5%Fe, 0.5%Si. The Al-8%Zn-3%Mg-1%Ca-0.5%Fe-0.5%Si (AlZnMg1CaFeSi) was preliminarily found promising since it showed a hi...

The effect of Mg on Ca movement between the sarcoplasmic reticulum (SR) and myofilament space (MFS) was studied in skinned muscle fibers by using isometric force as an indicator of MFS Ca. In Ca-loaded fibers at 20 degrees C, the large force spike induced by Ca in 1 mM Mg (5 mM ATP) was strongly inhibited in 3 mM Mg, and force development was extremely slow. After a brief Ca stimulus in 1 mM Mg...