Fluoride in aquatic systems is increasing due to anthropogenic pollution, but little is known about how this fluoride affects organisms that live in and around aquatic habitats. Fluoride can bioaccumulate in structures comprised of calcium carbonate, such as shells and skeletons of both freshwater and saltwater species as diverse as snails, corals, and coccolithophorid algae. In this article, i...

Scleractinian coral skeletons are made mainly of calcium carbonate in the form of aragonite. The mineral deposition occurs in a biological confined environment, but it is still a theme of discussion to what extent the calcification occurs under biological or environmental control. Hence, the shape, size and organization of skeletal crystals from the cellular level through the colony architectur...

Images captured under water are often characterized by low contrast, color distortion, and noise, hindering some visual tasks carried out on it. Despite remarkable breakthrough has been made in recent years, effective robust enhancement of degraded image remains a challenging problem. To improve the quality underwater images, we propose novel scheme constructing an adaptive contrast enhancement...

Previous experiments have proved that thermodynamically unstable calcium carbonate vaterite can exist for long periods in the yolk sac of a pigeon embryo. The aim of this article was to demonstrate the effect of in vitro mineralization of yolk sac fluid on calcium carbonate by direct precipitation. Experiments were conducted using pigeon yolk sac fluid and using lecithin extracted from pigeon y...

We propose a circuit extension handshake for Tor that is forward secure against adversaries who gain quantum computing capabilities after session negotiation. In doing so, we refine the notion of an authenticated and confidential channel establishment (ACCE) protocol and define pre-quantum, transitional, and postquantum ACCE security. These new definitions reflect the types of adversaries that ...

An experimental model that allowed differentiation between endogenously and exogenously derived urinary oxalate was used to assess the effect of different forms and doses of ingested calcium on oxalate absorption and excretion. In replication 1 (R-1), subjects participated in three oxalate load (OL) tests: baseline (OL alone), calcium carbonate (OL with concomitant calcium carbonate ingestion),...

Endothelial dysfunction underlies multiple cardiovascular consequences of chronic kidney disease (CKD) and antecedent diabetes or hypertension. Endothelial insults in CKD or end-stage renal disease (ESRD) patients include uremic toxins, serum uric acid, hyperphosphatemia, reactive oxygen species, and advanced glycation endproducts (AGEs). Sevelamer carbonate, a calcium-free intestinally nonabso...

BACKGROUND Bariatric surgery, especially Roux-en-Y gastric bypass, can cause serious nutritional complications arising from poor absorption of essential nutrients. Secondary hyperparathyroidism is one such complications that leads to increased parathyroid hormone levels due to a decrease in calcium and vitamin D, which may compromise bone health. AIM To compare calcium carbonate and calcium c...

All commercially available integrase inhibitors are 2-metal binders and may be affected by co-administration with metal cations. The purpose of this study was to evaluate the effect of calcium and iron supplements on dolutegravir pharmacokinetics and strategies (dose separation and food) to attenuate the effects if significant reductions in dolutegravir exposure were observed. This was an open-...

Inorganic carbonate in soil occurs predominantly as the sparingly soluble alkaline-earth carbonates, calcite (CaCOs) and dolomite (CaMg(CO,),). Calcite is usually the dominant form in active pedogenic environments (Doner & Lynn, 1977; Nelson, 1982). There are only a few reported occurrences of aragonite (CaCOs) and vaterite (CaCOs) in soils. Sodium carbonate and magnesium carbonate and hydroxyc...