Utilization of calcium carbonate particles from eggshell waste as coating pigments for ink-jet printing paper

The effective treatment and utilization of biowaste have been emphasized in our society for environmental and economic concerns. Recently, the eggshell waste in the poultry industry has been highlighted because of its reclamation potential. This study presents an economical treatment process to recover useful bioproducts from eggshell waste and their utilization in commercial products. We developed the dissolved air floatation (DAF) separation unit, which successfully recovered 96% of eggshell membrane and 99% of eggshell calcium carbonate (ECC) particles from eggshell waste within 2 h of operation. The recovered ECC particles were utilized as coating pigments for ink-jet printing paper and their impact on the ink density and paper gloss were investigated. The addition of the ECC particles as coating pigments enhances the optical density of cyan, magenta and yellow inks while decreasing the black ink density and the gloss of the coated paper.     

Addressing hERG activity while maintaining favorable potency,selectivity and pharmacokinetic properties of PPARδ modulators

One of the most commonly used strategies to reduce hERG (human ether-a-go-go) activity in the drug candidates is introduction of a carboxylic acid group. During the optimization of PPARδ modulators, some of the compounds containing a carboxylic acid were found to inhibit the hERG channel in a patch clamp assay. By modifying the basicity of the imidazole core, potent and selective PPARδ modulators that do not inhibit hERG channel were identified. Some of the modulators have excellent pharmacokinetic profiles in mice.     

Efficient generation of smooth muscle cells from adipose‐derived stromal cells by 3D mechanical stimulation can substitute the use of growth factors in vascular tissue engineering

Occluding artery disease causes a high demand for bioartificial replacement vessels. We investigated the combined use of biodegradable and creep‐free poly (1,3‐trimethylene carbonate) (PTMC) with smooth muscle cells (SMC) derived by biochemical or mechanical stimulation of adipose tissue‐derived stromal cells (ASC) to engineer bioartificial arteries. Biochemical induction of cultured ASC to SMC was done with TGF‐β1 for 7d. Phenotype and function were assessed by qRT‐PCR, immunodetection and collagen contraction assays. The influence of mechanical stimulation on non‐differentiated and pre‐differentiated ASC, loaded in porous tubular PTMC scaffolds, was assessed after culturing under pulsatile flow for 14d. Assays included qRT‐PCR, production of extracellular matrix and scanning electron microscopy. ASC adhesion and TGF‐β1‐driven differentiation to contractile SMC on PTMC did not differ from tissue culture polystyrene controls. Mesenchymal and SMC markers were increased compared to controls. Interestingly, pre‐differentiated ASC had only marginal higher contractility than controls. Moreover, in 3D PTMC scaffolds, mechanical stimulation yielded well‐aligned ASC‐derived SMC which deposited ECM. Under the same conditions, pre‐differentiated ASC‐derived SMC maintained their SMC phenotype. Our results show that mechanical stimulation can replace TGF‐β1 pre‐stimulation to generate SMC from ASC and that pre‐differentiated ASC keep their SMC phenotype with increased expression of SMC markers.     

Two decades of carbonate budget change on shifted coral reef assemblages: are these reefs being locked into low net budget states?

The ecology of coral reefs is rapidly shifting from historical baselines. One key-question is whether under these new, less favourable ecological conditions, coral reefs will be able to sustain key geo-ecological processes such as the capacity to accumulate carbonate structure. Here, we use data from 34 Caribbean reef sites to examine how the carbonate production, net erosion and net carbonate budgets, as well as the organisms underlying these processes, have changed over the past 15 years in the absence of further severe acute disturbances. We find that despite fundamental benthic ecological changes, these ecologically shifted coral assemblages have exhibited a modest but significant increase in their net carbonate budgets over the past 15 years. However, contrary to expectations this trend was driven by a decrease in erosion pressure, largely resulting from changes in the abundance and size-frequency distribution of parrotfishes, and not by an increase in rates of coral carbonate production. Although in the short term, the carbonate budgets seem to have benefitted marginally from reduced parrotfish erosion, the absence of these key substrate grazers, particularly of larger individuals, is unlikely to be conducive to reef recovery and will thus probably lock these reefs into low budget states.     

Studies on the possible role of cation exchange capacity in the soil preference of mosses

Summary Moss species with a different soil preference with respect to its acidity and carbonate content also differ in their cation exchange capacity (leaf, stem, rhizoid), the acidiphile-calcifuges having lower C.E.C. values than the neutrophile-calcicoles. The higher the C.E.C. value, the more the divalent cations calcium and magnesium tend to be adsorbed as compared to the monovalents sodium and potassium, from an equinormal tetracationic solution. The increase in divalent adsorption is mainly due to calcium. Considering this differential adsorption of calcium and in view of data in literature on membrane characteristics, it appears that among the studied cations calcium is an important factor in the observed soil preference through its presence in the cell wall adsorbed fraction and thus in the membrane environment. The authors are granted a scholarship ‘aspirant-vorser’ of the Belgian ‘Nationaal Fonds voor Wetenschappelijk Onderzoek’.     

The crustaceans burrow Sinusichnus sinuosus from the Oligocene-Miocene carbonate deposits of eastern Amazonia

Abstract

Sinusichnus Gibert 1996 Gibert, J. M. d. 1996. “A New Decapod Burrow System from the NW Mediterranean Pliocene.” Revista Española de Paleontología 11: 251–254. [Google Scholar] is recorded for the first time in the Oligocene-Miocene Pirabas Formation of Northern Brazil. In these Oligocene-Miocene carbonate deposits, Sinusichnus sinuosus is characterized by horizontal, highly regular sinusoidal burrow systems with T- and H-shaped branching points. The main difference between the S. sinuosus described herein and other occurrences worldwide is the anomalous diameter of the burrows (4 to 10?cm). These trace fossils occur in organic matter-rich, wackestone/packstone and laminated mudstones interbedded with boundstones deposited in an inner carbonate platform paleoenvironment. The exceptional size of the studied S. sinuosus could have been associated to the producer’s size, which may be attributed to construction by large crustaceans, similar to fossils found within the Pirabas Formation. Also, the sinusoidal morphology and retrusive spreiten could be a result of the fodinichnial/domichnial behavior.     

Key roles of pH and calcium metabolism in microbial carbonate precipitation

This paper reviews the general mechanismsof microbial carbonate precipitation and offersan alternative view on the role of calciummetabolism in this process, as well as on theoccurrence of species- and environment-specificcalcification.