Productivity in the Southern Oceans is iron-limited, and the supply of iron dissolved from aeolian dust is believed to be the main source from outside the marine reservoir. Glacial sediment sources of iron have rarely been considered, as the iron has been assumed to be inert and non-bioavailable. This study demonstrates the presence of potentially bioavailable Fe as ferrihydrite and goethite in...

In two montane watersheds that receive minimal deposition of atmospheric nitrogen, 15–71% of dissolved organic nitrogen (DON) was bioavailable in stream water over a 2-year period. Discharge-weighted concentrations of bulk DON were between 102 and 135 lg/l, and the C:N ratio differed substantially between humic and non-humic fractions of DON. Approximately 70% of DON export occurred during snow...

Iron and vitamin A deficiencies in childhood are public health problems in the developing world. Introduction of cereal-based complementary foods, that are often poor sources of both vitamin A and bioavailable iron, increases the risk of deficiency in young children. Alternative foods with higher levels of vitamin A and bioavailable iron could help alleviate these micronutrient deficiencies. Th...

We aim to evaluate the prevalence of vitamin D deficiency in patients with systemic lupus erythematosus (SLE) and investigate the association between total, free and bioavailable vitamin D serum concentrations and disease activity. Patients with SLE (ACR 1997) consecutively seen at UNIFESP's outpatient's clinics had disease activity measured after clinical and laboratory evaluation using SLEDAI...

The effect of smoking on androgen levels is important given the recent interest in the link between low levels of androgens and the development of cardiovascular disease. Numerous studies examining the effects of cigarette smoking on the levels of total and free testosterone have reported conflicting findings, but there has been no accurate assessment of the effects of cigarette smoking on the ...

CONTEXT In postmenopausal women, endogenous bioavailable testosterone (T) and estradiol (E2) have been positively associated, and SHBG has been negatively associated, with incident type 2 diabetes (T2DM). Previous studies have not explored possible factors explaining these relationships. OBJECTIVE Our objective was to examine the association of endogenous sex hormones with incident T2DM in po...

UNLABELLED Symptoms of testosterone deficiency and concentrations of testosterone (T) and bioavailable testosterone (BT) were studied in 35- and 45-year-old men. METHODS A questionnaire, was sent to all 35- and 45-year-old men in Linköping, Sweden (n=1998). The questionnaire has earlier been used for 55- to 75-year-old men and included demographic data, medical history, different symptoms pos...

Heavy metals are considered as the most dangerous water contaminants because of their possibility of bioaccumulation and toxic effects. This study tried to investigate the bio-availability of heavy metals in terms of Ni, Zn, Cu, Fe, Hg, Cd, and Pb in the sediment during dry seasons in Aras River basin located in Ardabil Province, north-west of Iran. Also the metal concentration in the skin and ...

Heavy metals are considered as the most dangerous water contaminants because of their possibility of bioaccumulation and toxic effects. This study tried to investigate the bio-availability of heavy metals in terms of Ni, Zn, Cu, Fe, Hg, Cd, and Pb in the sediment during dry seasons in Aras River basin located in Ardabil Province, north-west of Iran. Also the metal concentration in the skin and ...

      A major hurdle in pharmaceutical formulation is water insolubility of most of drugs affecting their stability and bioavailability. If the drug is also insoluble in organic medium, it is difficult to deliver it in a sufficiently bioavailable form and hence it is a great challenge to formulation researchers to overcome such difficulty. Although some approaches are available for enhancing th...